REPAIR YOUR COMPUTER QUIKLY
Computer Lab Manager
Training Course
NOTE: IMAGES ARE NOT DISPLAYED
Computer Lab Manager
Training Course
Module 1 Table of Contents
1. Introduction
2.2.Hardware
2.3.Software
3.1.Why Maintain?
5.9.Managing E-Waste
5.10.
Assignment/Activities
8.
Bibliography
Module 1 Text
The Computer Lab Manager Training Course was developed
by Zambia Pacific Trust in collaboration with a variety of organizations
working on IT related development projects in Zambia. While these projects are in several different
sectors (health, education, agriculture and community), all of the
organizations recognized the need to increase the number of people who have
training in computers past the standard level of a computer user. A particular need that was identified was for
individuals who could maintain dynamic and well functioning computer labs and
other centers for IT use within a particular project. Therefore, a multi-faceted training course
was developed to meet these needs including both the “hard skills” of computer
maintenance, repair, and networking and the “soft skills” of management,
leadership, communication and instruction.
Readers may find more emphasis shown on educational projects, since that
is the area of Zambia Pacific Trust’s experience. However, most topics discussed apply equally
well in the other sectors where IT is used.
The resource books for these modules are designed to
be used as a part of an instructor-led four module course, with each course
including both a distance (online) instruction component and a one week
face-to-face workshop. This resource
book is written to accompany the first of the four modules listed below.
Module 1: Computer Maintenance, Troubleshooting and
Repair
Module 2: Management and Leadership
Module 3: Instruction, Facilitating IT Use and IT in
Education
Module 4: Networking, Communication and Web 2.0
The target audience for this training course is adult
learners who already have intermediate computer user skills and significant
experience using computers. Ideally,
participants are already employed as computer lab managers, computer project
coordinators or Internet café managers.
While the course is tailored to those working in educational or
community organizations, the course is still valuable for those working in a
similar capacity in the private sector.
These learning materials are also valuable for people
who are not involved in a formal course, but instead are studying independently
to become computer lab managers or improve their skills as computer lab managers. Learners who are using these materials for
self study are encouraged to make the training as hands-on as possible,
performing as many of the assignments and activities as they can practically
achieve.
Throughout the computer lab manager training course, a
strong emphasis is placed on practical learning. Learners will find that theoretical topics
are covered quite briefly and more attention is paid to topics that relate to
activities that the learners will perform in their computer labs. In the distance learning portion of each
module, the majority of the assignments require the learners to think and then
act. This includes using a local
computer lab (both the computers and the community of people found there) as an
opportunity to try out skills, test out ideas and implement improvements. The face-to-face workshops also will
emphasize active learning. Learners are
asked to participate in discussions and role plays, and are given many
opportunities to learn and practice technical skills using the available omputers.
A computer is a fabulous instrument that turns human
inputs into electronic information that it then can store or share/distribute
through various output devices. A
computer performs (if instructed to do so) the steps shown in the diagram below,
using information that a user provides (such as a typed sentence):
All of the equipment (hardware) and the instructions
(software) needed to complete the above steps are described in the next
section.
Amazingly, the information that the user inputs into a
computer is processed so that it becomes a simple code made up of only two digits:
zero and one! For all its complexity, a
computer is only able to handle these two choices. This is because it is based on electrical
signals that have only two options (such as either on or off). But computers compensate for this very simple
code by using it in huge quantities. A
single unit of this zero/one code is called a bit. Grouping 8 bits together makes a unit of
information called a byte. Typing a single
page of typed text on a computer requires a minimum of about 20 kilobytes (20
KB or 20,000 bytes) of information to be stored. Good quality digital photographs are usually
1 megabyte (1 MB or 1,000,000 bytes) or larger.
So a computer is a very “busy” machine indeed!
2.2.1.
Basic Hardware
Components
Hardware is the physical equipment needed for a
computer to function properly. The basic
hardware parts are briefly described here.
Many computer lab managers will already have been exposed to computer
hardware through other courses, but those desiring additional information can
find it in a variety of texts and online sources. A desktop computer is used in the photos, but
all of this equipment is also found (in a more compact arrangement) in a laptop
computer.
Case. The
computer case (also called a tower or housing) is the box that encloses many of
the parts shown below. It has attachment
points, slots and screws that allow these parts to be fitted onto the case. The case is also sometimes called the CPU,
since it houses the CPU (central processing unit or processor), but this
designation can lead to confusion.
Please see the description of the processor, below.
Power
Supply. The power supply is used to connect all of
the parts of the computer described below to electrical power. It is usually is found at the back of the
computer case.
Fan. A fan is needed
to disperse the significant amount of heat that is generated by the
electrically powered parts in a computer.
It is important for preventing overheating of the various electronic
components. Some computers will also
have a heat sink (a piece of fluted metal) located near the processor to absorb
heat from the processor.
Motherboard.
The motherboard is a large electronic board
that is used to connect the power supply to various other electronic parts, and
to hold these parts in place on the computer. The computer’s memory (RAM, described below)
and processor are attached to the motherboard.
Also found on the motherboard is the BIOS (Basic Input and Output
System) chip that is responsible for some fundamental operations of the
computer, such as linking hardware and software. The motherboard also contains a small battery
(that looks like a watch battery) and the chips that work with it to store the
system time and some other computer settings.
Drives. A computer’s
drives are the devices used for long term storage of information. The main storage area for a computer is its
internal hard drive (also called a
hard disk). The computer should also
have disk drives for some sort of removable storage media. A floppy
disk drive was very common until recent years, and is still found on many
older desk top computers. It was
replaced by CD-ROM and DVD drives, which have higher storage
capacities. The current standard is a DVD-RW drive, which can both read and
write information using both CD and DVD disks.
The USB ports (described later) on a computer can also be used to
connect other storage devices such as flash
drives and external hard drives.
Cards. This term is
used to describe important tools that allow your computer to connect and
communicate with various input and output devices. The term “card” is used because these items
are relatively flat in order to fit into the slots provided in the computer
case. A computer will probably have a
sound card, a video card, a network card and a modem.
RAM. RAM is the abbreviation
for random access memory. This is the
short term memory that is used to store documents while they are being
processed. The amount of RAM in a
computer is one of the factors that affect the speed of a computer. RAM attaches to the motherboard via some
specific slots. It is important to have
the right type of RAM for a specific computer, as RAM has changed over the
years.
Processor. The processor
is the main “brain” of a computer system.
It performs all of the instructions and calculations that are needed and
manages the flow of information through a computer. It is also called the CPU (central processing
unit), although this term can also be used to describe a computer case along
with all of the hardware found inside it. Another name for the processor is a computer
“chip” although this term can refer to other lesser processors (such as the
BIOS). Processors are continually
evolving and becoming faster and more powerful.
The speed of a processor is measured in megahertz (MHz) or gigahertz
(GHz). An older computer might have a
processor with a speed of 1000 MHz (equivalent to 1 GHz) or lower, but processors
with speeds of over 2 GHz are now common.
One processor company, Intel, made a popular series of processors called
Pentium. Many reconditioned computers
contain Pentium II, Pentium III and Pentium 4 processors, with Pentium 4 being
the fastest of these.
Peripheral
hardware. Peripheral hardware is the name for the
computer components that are not found within the computer case. This includes input devices such as a mouse, microphone and keyboard, which carry information from
the computer user to the processor, and output devices such as a monitor, printer and speakers, which display or transmit
information from the computer back to the user.
2.2.2.
Computer Ports
The peripheral hardware mentioned above must attach to
the computer so that it can transmit information from the user to the computer
(or vice versa). There are a variety of
ports present on a computer for these attachments. These ports have gradually changed over time
as computers have changed to become faster and easier to work with. Ports also vary with the type of equipment
that connects to the ports. A computer
lab manager should become familiar with the most common ports (and their uses),
as described below.
Serial Port.
This port for use with 9 pin connectors is no
longer commonly used, but is found on many older computers. It was used for printers, mice, modems and a
variety of other digital devices.
Parallel
Port. This long and slender port is
also no longer commonly used, but was the most common way of attaching a
printer to a computer until the introduction of USB ports (see below). The most common parallel port has holes for 25
pins, but other models were also manufactured.
VGA.
The Video Graphics Array port is found on most
computers today and is used to connect video display devices such as monitors
and projectors. It has three rows of
holes, for a 15 pin connector.
PS/2. Until
recently, this type of port was commonly used to connect keyboards and mice to
computers. Most desktop computers have
two of these round ports for six pin connectors, one for the mouse and one for
the keyboard.
USB.
The Universal Serial Bus is now the most
common type of port on a computer. It
was developed in the late 1990s as a way to replace the variety of ports
described above. It can be used to
connect mice, keyboards, printers, and external storage devices such as DVD-RW
drives and flash drives. It has gone
through three different models (USB 1.0, USB 2.0 and USB 3.0), with USB 3.0
being the fastest at sending and receiving information. Older USB devices can be used in newer model
USB ports.
TRS. TRS
(tip, ring and sleeve) ports are also known as ports for mini-jacks or audio
jacks. They are commonly used to connect
audio devices such as headphones and microphones to computers.
Ethernet.
This port, which looks like a slightly wider
version of a port for a phone jack, is used to network computers via category 5
(CAT5) network cable. Although many
computers now connect wirelessly, this port is still the standard for wired
networked computers. Some computers also
have the narrower port for an actual phone jack. These are used for modem connections over
telephone lines.
2.3.1.
Software Types and Categories
As mentioned in section 2.1,
computer software is the term used for the instructions that have been
programmed to allow a computer to process information. Software comes in three main categories,
described below:
Operating
Systems. These are the basic software programs that are
needed to for a computer to work. They
give a computer the basic information needed for it to process and store information. Currently all common operating systems are
also graphical user interfaces (GUIs) which means they use graphics to help the
user to easily input instructions, and open other programs. The most common operating systems (OS) are
the Windows family of operating systems, from Microsoft. A computer lab manager is likely to encounter
Windows 2000, Windows XP, Windows Vista and Windows 7 (the most recent Microsoft
OS) in a computer lab. Other operating
systems are described in the next section.
Utility Software. This
is a broad category of programs that allow a computer to perform tasks that
aren’t a part of the operating system, but are still practical and useful. For example, a utility might instruct a
computer on how to copy (burn) information to a CD-ROM disk, or it might be an
anti-virus program (see section 3.3).
Productivity
Software. This is one term used to describe the type of software
used to perform standard office computer tasks.
Word processing, presentation, spreadsheet and database software are all
common examples of productivity programs.
The most common set of productivity programs is Microsoft Office,
offered by the Microsoft Corporation.
2.3.2.
Proprietary Software vs. Open Source Software
The Microsoft operating system and productivity
software packages mentioned above are very common and used around the world in
business and education. The Apple
Corporation also has very popular and successful operating systems used for
their Macintosh computers. Despite the
success of these software products, they aren’t the best choices for everyone. They are proprietary, which means that their
use and modification are restricted. They
can be quite costly to buy licenses for, and they are not adaptable to meet
local needs. Some users, particularly in
developing countries, illegally use unlicensed (also known as pirate) copies of
this software. This is legally unwise,
and can also keep the user from accessing important software updates.
Users who cannot afford proprietary software or prefer
software that can be locally modified, can choose to use open source (often
called free and open source or FOSS) software.
For most of the standard computer uses, an open source software option
is available. This includes the Linux
family of operating systems (which includes Ubuntu, a common operating system
in African countries) and the OpenOffice.org productivity programs. The Source Forge website (www.sourceforge.net) is a good resource
for finding and downloading open source programs. While open source software often does not
come with professional support available, there are user groups found on the Internet
who can offer assistance to puzzled users.
This training module does describe how to perform some tasks using the
Ubuntu operating system, but does not provide thorough coverage. Further assistance with Ubuntu is available
through the website: http://help.ubuntu.com.
When first setting up a computer lab, the steering
committee for a computer project should discuss the benefits of both
proprietary and open source software and make an informed and intentional
choice on which way to go. The computer
lab manager should then make sure that he or she is aware of all policies
related to software choices.
It is possible that a computer project will choose to
use proprietary software for some purposes and open source software for
others. For example, a project might be
able to obtain used computers that have a Windows operating system legally
installed (such as through a Microsoft Authorized Refurbisher) but these
computers do not include other Microsoft programs. In this case the organization might choose to
continue to run Windows on its computers, but choose open source options for
all utility and productivity software.
Please Note: Throughout this module there are assignments
that require a learner to have access to computers and the Internet. Students who are not already working as
computer lab managers may find performing these assignments to be
difficult. These learners are encouraged
to consult with the staff of a local computer project or Internet café to gain
access to equipment and the Internet. It
is even possible that short term internships could be arranged that would be
beneficial to both the learner and the computer project.
2.4.1. Study the exterior of a particular computer. See if you can identify the power supply, the
drives, and all of the ports described in this chapter.
2.4.2. Find a broken or disused desktop computer. Figure out how to open up the case. Identify all of the hardware components that
have been described in this chapter.
2.4.3. What type of software is used on the computer you use
most frequently? Identify the operating
system, the productivity software, the Internet browser and the anti-virus
software. For each of these also state
whether they are proprietary or open source.
If you are having trouble finding out information about some of your
programs, here are some tips: To find
out about your computer’s operating system, right click on the Computer or My
Computer icon from your desktop or Start menu.
Choose Properties. To find out
about a productivity program, open that program and then find a menu that
includes the word “About”. To find the
About screen in Microsoft Office 2007, click on the Microsoft Office Button, then
click on Options à Resources à About.
2.4.4. How much RAM does the computer you use most frequently
have? Also how fast is the processor on
this computer? To find this information,
right click on the Computer or My Computer icon from your desktop or Start
menu. Choose Properties.
2.4.5. Have a discussion with a manager of a local computer
lab about computer operating systems.
What operating systems are being used in that computer lab and why? What factors went into the decision to choose
an operating system?
2.4.6. Workshop Activity:
In a group, observe the exterior of computer. How many ports and hardware devices can your
group identify? Ask the instructor for assistance with any items that cannot be
identified.
2.4.7. Workshop Activity: In a group, open up the case of a
computer. Identify all of the hardware
components that have been described in this chapter.
2.4.8. Workshop Activity: Participate in a group discussion
or a debate on the advantages and disadvantages of using open source software.
2.4.9. Workshop Activity:
Experiment with an operating system that you are not familiar with. See if you can figure out how to change the
background, open and close windows, open and close programs, and perform any
other computer tasks that you frequently perform with other operating systems.
Think of a computer as being like a human body. We are advised to perform certain tasks to
keep our body in good shape. These
maintenance tasks such as eating well, avoiding some harmful activities and
getting exercise keep our body in good condition. If we don’t maintain our bodies, we might end
up in the hospital with problems that result from the abuse such as high blood
pressure from eating too much salt, obesity from not exercising or lung
problems from smoking. Similarly, if we
allow our computers to intake harmful materials (such as dust) and programs
(such as viruses) and we don’t keep our software in good condition (updated)
then the computer may also end up with significant problems that are then
harder to deal with. Proper maintenance
of a computer, on the other hand, can keep it running smoothly for years and
years. Some of the different categories
of computer maintenance are described below.
Software programmers gradually develop updates for
their software packages as they discover problems with the software and design
tools to address or fix these problems.
This can be true for any of the types of software described in section 2.3, but is typically most common and important for
operating systems. It is important for a
computer user to find and install software updates in order to have well
performing computers. Updating software
can be done in a variety of ways, described below.
·
Automatic Updates. If a computer is on a
reasonably fast Internet connection, the easiest way to keep it up to date is
to allow the programs to automatically check for updates and download and
install them as needed. When setting up
a new computer with Microsoft Windows, this is the choice that the software
recommends. It does not require any
action on the part of the user, and results in a computer system that is
current. To turn on automatic updates
for a Windows operating system, find the Systems and Maintenance options in the
Control Panel.
·
Automatic Alerts for Updates. If a computer
is connected to the Internet, but the connection is slow at some times of the
day, another option is to have the computer automatically check for updates but
not download or install them until the user elects to do so. For Microsoft Windows computers, if this
option is selected, an alert appears in the computer’s system tray stating that
there are updates waiting, and then the user can wait until the Internet is
faster to install these updates.
·
Manual Updating. A computer user can also turn
off all automatic update checking and choose to manually check for
updates. For a computer that is rarely
connected to the Internet, this would be a good option as long as the user
remembered to check when connecting to the Internet. Also some programs do not have automatic
update options, and can only be updated in this manner. A program usually has a menu item titled
“check for updates” that a user can click on when connected to the Internet.
·
Offline Updating. If a computer is in a location
that never has access to the Internet, a computer lab manager will need to
download updates from a computer that is connected to the Internet and then
transfer them (via a disk or flash drive) to the computer in question to be
installed. This option is also useful if
a computer lab has several computers that all need the same update. Instead of
having each computer download the update separately, one computer could
download the update and then it could be shared amongst all of the computers. Offline updates for operating systems can
easily be found through Internet searches.
Updates to download for Windows computers can also be found through www.microsoft.com/downloads.
Viruses, spyware and other malicious programs can all
be referred to together as malware.
Malware prevention is a significant maintenance task for a computer lab
manager. Without vigilance, a computer
lab will quickly become prey to malware.
It will spread from machine to machine causing the computers to slow
down, work improperly or possibly even stop working altogether. The computer lab manager needs to make sure
that all of the computers have anti-virus software installed, and that this
software is set up so that it regularly updates its virus databases and scans
the computers. The tip box here gives more
details on how to do this.
The computer lab manager also needs to have strict
policies in place to prevent virus infection.
Since viruses are easily spread by the use of flash drives, the policy
could prohibit the use of flash drives, or require them to be scanned by a
staff member before use. Another policy
to consider is the prohibition of downloading, since unsuspecting users can
accidentally download malware. A
firewall that blocks dangerous downloads can also be useful.
There are some common hardware problems that can be
avoided, or at least made less frequent by taking particular preventive
measures with computers. These
preventive measures are listed below.
Dust
Control. Dust is very harmful for computer parts. Excess dust can cause mechanical failures,
particularly on computer components with moving parts. Minimizing dust in a computer lab is an
important part of computer maintenance.
Computer lab cleaning advice is discussed further in Module 2. The computers themselves should be regularly
dusted (wiped with a dry cloth or duster) and if the computers are housed in a
particularly dusty area, the use of dust covers (when the computers are turned
off) is advised. In addition, when a
computer case is opened for other repairs, the dust that has built up inside
the case should be blown out. This works
best with forced air. Different
mechanical and electrical tools are available to compress air. These tools are described in section
5.7.1.
Heat
Control. Computer parts, in
particular the CPU, produce a large amount of heat while operating. It is important for this heat to dissipate,
so that the computer is not damaged by overheating. Computers do have fans and heat sinks, but
these will only work well if the air flow to the computer is not blocked. This means, for example, that a laptop
computer should not be left running for any length of time on a soft surface
(like a sofa) that conforms around it, and a desktop computer case should not
be used while in an enclosed cabinet. In
addition, it is ideal that the computer lab temperature be kept low. Using air conditioners is a good option,
since the windows can also be kept closed to minimize dust, but many computer
projects cannot afford air conditioners or the associated electricity
costs. Therefore curtains (to reduce the
heat of the sunlight), open windows and fans are often the best alternatives,
although their use requires increased vigilance against dust.
Surge
Protection. In many countries, the electrical supply does not have
a uniform (well controlled) voltage.
Voltage is also variable due to surges that occur, particularly during
thunderstorms and when power is returning after an outage. Voltage surges can be very damaging to
computers and other electrical components, and it is important to protect
against these events. The simplest form
of surge protection is to purchase surge protecting power (adaptor)
strips. These devices contain 4 or 5
outlets that are protected by a fuse that is blown in case of a power
surge. The quality of these power strips
varies, though, and they cannot be guaranteed to be the safest form of surge
protection. A second form of surge
protection is a surge suppressor that is installed where the main power enters
a computer lab. These devices, though
more expensive, are of higher quality and will protect all of the electrical
components plugged in to electrical sockets within the room. A third option to consider is to purchase
uninterrupted power supplies (UPSs) to share between every two computers in a
computer lab (since a UPS includes six to ten electrical sockets). A UPS regulates the voltage sent to the
sockets located on the UPS itself, and also contains a battery that allows for
continued operation of a computer after a power outage. Depending on the UPS model and the amount of
equipment attached to the UPS, the battery might last for an hour or for just a
few minutes, but even just a few minutes allows enough time for the user to
save their work and shut the computer down properly.
Laptop
Maintenance Issues. For computer
labs using laptop computers, there are a couple of additional issues to be
aware of that can affect the lifespan of the computer. Because laptop computers are moved around
from place to place and handled more roughly than desktop computers, they are
more likely to have hardware problems develop.
One problem area, for example, is in the AC adaptor port. If it is found in the back of a laptop
computer, it is easy for the computer user to tilt the laptop backwards and
unintentionally place pressure on the AC adaptor as it is forced against the
table top. The AC port (and any other
port located on the back of a laptop) can be easily damaged from this stress. Therefore computer users should be instructed
on the proper technique to use when picking up a laptop computer. A second problem area for laptop computers is that
the screws on the laptop body gradually become loosened as the computer is
moved about. A computer lab manager
should periodically (perhaps twice a year) tighten the screws on all laptop
computers.
Peripheral hardware will also last longer if it is well
maintained. For peripheral hardware such
as printers, projectors and external drives, all of the advice above about
heat, dust and power surge control is still relevant and important. In addition, there are some tips below for
using printers and projectors that will help these pieces of equipment work
efficiently and last a long time.
Proper Use
of an LCD Projector. An LCD projector is a valuable tool for making
presentations and assisting in training courses. However, these projectors are very expensive
to purchase. If a computer project has
had the good fortune of being able to purchase a projector, it is important
that every effort be taken to make sure that the projector is kept in good
repair. Some suggestions are shown here:
·
Store and carry
the projector in a padded case. This
will keep dust out of the projector and cushion it in case of rough handling.
·
Keep a designated
surge protecting power strip (adaptor strip) with the projector, and make sure
that all projector users know the importance of using the projector with surge
protector.
·
Make sure that the
appropriate procedure for shutting down the projector is used, and inform all
projector users about the procedure. For
most projectors, the proper shut down procedure includes not unplugging the
projector until the cooling process is complete. This is indicated by a status light changing
color, or a fan turning itself off. It
is important to allow the projector bulb to cool completely in order to extend
the life of the bulb.
It is particularly important to note that the
projector bulb, which is the most expensive part in a projector, will wear out
and need to be replaced eventually.
Projector bulbs can cost half the price of buying a new projector! A computer project will need to make a plan
for bulb replacement, ideally even keeping a spare bulb on hand.
Efficient
Use of a Printer. Most computer labs will have at least one
printer for the use of the computer lab manager and selected computer lab
users. Printers are a great resource,
but if not controlled well they can be overused. This puts unnecessary wear on the printer,
and also uses up expensive ink and paper.
It would be wise for a computer lab manager to have in place some
policies about what sort of material can be printed, and when color ink use is
allowed. Users should also be instructed
to preview their work before printing, to avoid printing unnecessary
pages. In addition, many printers have
different printing settings that control the quality of the printouts and thus
the amount of ink used. Inkjet printers,
for example, usually have an option for “draft” or “fast” printing that uses
significantly less ink, but still looks reasonably good. To find this option when printing a document,
select Print from the File menu (or the Office Button in MS
Word 2007). When the print menu opens,
there will be a Properties button
next to the selected printer. Clicking
here will bring up choices such as the print quality and whether the printout
should be in color or black and white.
3.6.1. Find and open the anti-virus software on a
computer. Check to see if the virus
database is up to date. If it isn’t,
update the software and also see if there is an option to setup the program to
automatically look for updates. Also see
if there is an option that allows you to schedule regular (daily) scans.
3.6.2. Go to a local computer lab and ask the computer lab
manager about maintenance tasks. What tasks does he or she do to keep the
computers in good condition, and how often are these tasks performed (daily,
weekly, monthly or yearly)? If the
computer lab manger does not have any maintenance systems in place, instead
report your recommendations for computer maintenance.
3.6.3. Open the case of a computer and observe the dust
inside. What tools do you have at hand
that could be used to safely remove that dust without damaging the
equipment? Experiment with the equipment
that is available to you and report your findings.
3.6.4. Figure out how to set up a printer so that the default
print settings are black and white (not color) and “draft” or “fast” printing.
3.6.5. Workshop Activity:
Observe a demonstration on how to properly set up and shut down an LCD
projector. Make sure that you have an
opportunity to practice these techniques yourself sometime during the workshop.
3.6.6. Workshop Activity:
Using provided tools, find and tighten all of the screws on a laptop
computer.
3.6.7. Workshop Activity: Participate in a role play (and
follow up discussion) in which a lab manager tries to convince a person with a
home computer to bring it in to the lab for updates.
What should be done before using a new computer? This depends very much on where the computer
came from and what software was already installed. If a computer project receives new computers
complete with an operating system and all productivity software, little needs
to be done before using the computers.
The computer lab manager should check, however, to make sure the
computer is fully set up to meet the needs of the project. Some items to investigate are listed here:
·
Does the computer
already have all of the programs that are desired for the project? This could include, for example, an Internet
browser, productivity (office) software, antivirus software or perhaps some
educational software.
·
Does the computer
already have all of the files that are desired for the project? For example, an educational project might
want to have an encyclopedia or some educational presentations loaded on all of
the computers.
·
Does the computer
have separate user accounts with passwords?
This is a good way to control what access some users have to particular
programs, files or settings. See section 4.5 for more information. Another option to consider is installing and
using Microsoft SteadyState as a way to control what part of a computer certain
users can access (see Module 2, section 6.2.4 for more information).
A partitioned hard drive is one that has two (or more)
different sections for storage of different types of information. In some cases, one partition is used to store
the operating system and related files, while the other partition is used to
store user documents and settings. This
partitioning is valuable in cases when the hard disk has not failed, but the
partition with the operating system needs to be reformatted due to some sort of
localized problem. Then the computer user’s
documents and settings are not lost in the process. This sort of partitioning is usually done
when installing a computer operating system.
Computer lab managers can see the tip box in the next section for more
information on this process.
A computer lab manager can, however, create a new
partition at any time. If a new computer arrives with an operating
system installed but without a separate partition, the computer lab manager may
want to add one or two partitions. A separate partition can also be used by a computer
lab manager that would like to have two different operating systems on the same
hard drive, with one operating system loaded onto each partition. The tip
box here describes the process for creating a partition after an
operating system has already been installed.
If a computer project receives a new computer with no
software or with an unlicensed operating system, the computer lab manager will
need to install a new operating system. The
computer lab manager will need to choose between installing an open source
operating system (such as Ubuntu) or go with a proprietary operating system
(such as Microsoft Windows). While legal
copies of the most current Microsoft operating system (Windows 7 in 2010) are expensive,
a computer project may be able to find less expensive or free copies of older
versions of Windows, through a Community Microsoft Authorized Refurbisher (MAR). Some computer refurbishing centers in
developing countries are MARs. Please
see the website: www.microsoft.com/communitymar.
An operating system should be installed from a CD-ROM
or DVD disk. Before installation, the
computer lab manager needs to set up the computer so that it boots from the CD
or DVD drive first. This is the default
arrangement for newer computers, but older computers may boot first from the
floppy drive. After installing the new
operating system, the lab manger needs to be sure to change this back again to
the standard boot order. Details on how
to change the boot order and how to install an operating system are shown in
the tip
box here.
Knowing the proper method for installing and uninstalling
programs is important for any computer lab manager. Consider the situation, for example, when a
computer lab manager has been using fee-based antivirus software, but the free
trial subscription has expired. He or
she has decided to install free anti-virus software, rather than pay a
subscription fee for the original software, but needs to know how to uninstall
the initial anti-virus software first.
It is possible that if the original anti-virus software remains, it will
cause conflicts with the new anti-virus software, either preventing it from
functioning properly or slowing down the computer. Another reason it is useful to know how to
uninstall software, is to know how to respond when a computer lab user has
downloaded software that is unnecessary, inappropriate or slowing down the
computer. The steps for properly
uninstalling software are shown in the tip box here.
Installing software is typically easier than
uninstalling. The Add/Remove programs
screen can be used to install software, but most software will automatically
install once you open its installer program.
It is important, however, that a
computer lab manager make sure that he or she is installing software that is
beneficial for the computers, compatible with the current operating system and
will not slow down the functioning of the computers. A good way to find these programs is through
the C-Net website, www.download.com. More details are included in the tip
box here, which uses touch typing practice software as an example.
A user account is a set of information that is used by
a computer’s operating system to designate the settings that a particular user
prefers (such as desktop background or icon size), control what files and
folders a user can access, and control what changes a user is permitted to make
to a computer. After a new operating
system has been installed on a computer, the user is required to set up an
initial user account. This account is by
default an administrator account, which means that the user of this account has
the ability to access and change all computer settings, and install and
uninstall programs as desired. In most
cases, a computer lab manager will not want all of the other lab users to also
have these privileges and will therefore want to set up more restricted user
accounts for other computer users.
Depending on the type of computer project, the lab manager might want to
set up general accounts for all users of a certain type (such as an account
called “students” or “clients”) or they might want to set up specific password
protected accounts for individual users.
User accounts can be easily set up by a lab manager
who is logged into a computer using an administrator account. For a Windows computer the lab manager would
select Start à Control Panel à User Accounts. On a computer running the Ubuntu
operating system the lab manager would go to the main menu and choose System à Administration
à Users and
Groups. Once there, the lab manager
will able to set up the account and choose the privileges for those users. For Windows computers, the “standard” account
type should be chosen for all users that the lab manger does not want to have
administrative privileges. The lab
manager can also log in to his or her administrative account on a computer to
remove users or change the passwords on user accounts as needed to control
access.
4.6.1. Is the computer you usually use partitioned? Follow the instructions in the “Tips for
Partitioning a Hard Drive” tip box to the point where you can see what
partitions are already there and what their sizes are. If your computer is already partitioned, what
sorts of files or programs are stored on each partition? See if you can find this out by opening My
Computer.
4.6.2. Following the steps in “Tips for Uninstalling Software”
tip box, find and uninstall a bit of unnecessary software that you find on your
computer. If the computer is not yours,
or if you aren’t sure which software is unnecessary, ask for assistance and
permission first.
4.6.3. Explore the www.download.com
website. Can you tell the difference
between sponsored (paid advertising) links and the programs that are
recommended by CNET? Summarize your
findings. Also browse through the
different categories of programs. See if
you can find some that would be useful for a computer project in your area.
4.6.4. Set up a new user account on a computer and then log
into the computer using this account.
How is the appearance different and how are the privileges different?
4.6.5. Workshop Activity: As a group, find a list of
installed software on a computer (for Windows computers this can be done
through the Add/Remove Software tool in the Control Panel). Review the list and discuss what each
software program does. Determine whether
or not any of these programs should be removed from the computer.
4.6.6. Workshop Activity:
As a group, install a new operating system on a test computer.
4.6.7. Workshop Activity: As a group, discuss what types of
software are needed for a new computer.
Develop a list of software that would work well in a computer project in
your area. If time allows and the
software is available, install all of these programs on the computer used in
the previous activity.
This section of Module 1 is designed to empower the
computer lab manager to take care of minor computer problems. Without the knowledge here, many lab managers
will end up letting computers sit idle that could be easily put back into
service, or paying for expensive repairs that could have been handled locally. There will still be times when computers fail
and need to be sent out for repair by an expert, but those times should be few
and far between.
Many of us have had an experience with a computer in
which we open a program, and then find that we are waiting for over a minute
for the program to actually open. Some
of us have also had the experience of turning on a computer and then having to
wait several minutes for the computer to fully start up and load all of the
features that we are accustomed to seeing on the desktop. There can be several reasons for this sort of
slow speed, and many of these reasons are due to problems that can be easily
addressed. Several possible problems and
the strategies for addressing them are described in the sections below. Please note that software solutions are
discussed before hardware solutions since the software solutions are usually
the right place to start for computers that have gradually decreased in
performance over time. In some cases, however,
such as much older computers with small amounts of RAM and slow processors, the
hardware solutions will be more effective.
5.1.1.
Hard Disk Fragmentation
Over time, all computer hard disks become
fragmented. Fragmentation is when files
are stored in different “pieces” in different places on a hard drive, depending
on what storage space was available when the file was last modified. As the amount of free space on a hard drive
decreases, typically the fragmentation increases. Accessing files becomes slower because the
computer has to look around in different places on the hard drive to find the
different pieces of a file. To address this
problem, a hard drive should be defragmented.
Defragmenting can also become a regular maintenance task for heavily
used computers to keep them performing well.
Most computers come with a defragmentation program installed. On a Windows computer it should be found in Start à All Programs
à Accessories à System Tools. If no defragmenting program is found there,
some free defragmenting programs are available from www.download.com.
5.1.2.
Excess/Unused Files
As a hard disk becomes full, a computer’s performance
is reduced. It takes more time to find
and access needed files, and defragmentation is not as successful due to a lack
of free space to temporarily move files to while they are being rearranged. For best performance, there should be at
least 1 GB of free space on the computer’s hard disk. Therefore, it is wise for a computer user not
to keep files that are no longer needed.
Files that have been stored in a user’s documents folder that are no
longer needed (such as extra photos or older versions of documents) are best
deleted individually by the user. A
computer lab manager should also have a policy and procedure for regularly
deleting old files created by computer lab users on shared computers. In an educational lab, for example, the lab
manager could announce that student files are deleted at the end of every term,
unless the student makes special arrangements to preserve his or her work.
Sometimes there are other files, such as temporary Internet
files, that are stored on a computer without the user knowing it. To delete these sorts of files, perform both
of the following techniques:
·
Disk Cleanup. In a Windows computer the Disk Cleanup
utility is found in Start à All Programs
à Accessories à System
Tools. It scans a hard disk for
unnecessary files, and then (with the user’s permission) removes these files.
·
Deleting Browsing History. When using
the Internet, the browser stores the recent history of the web pages that the
user has viewed, in order to make it easier to find and load these web pages
again. The browser also stores other
small bits of information such as data entered into forms and usernames or
passwords if a user has asked a web page to “remember me” (although this is not
a good idea for shared computers). This
stored information can be easily deleted.
In Mozilla Firefox, choose Clear
Recent History from the Tools
menu. In Internet Explorer, choose Delete Browsing History from the Tools menu.
Excess software, particularly if it is software that
loads when the computer is booting up, can certainly slow performance. If a user is certain that a particular
program is not used and is not needed for the computer to function properly,
then this software can and should be deleted, as described in section
4.4. It is also possible to stop
some software from automatically starting up when the computer boots. For computers running Windows operating
systems, the System Configuration Utility can be used to perform this task. From the Start
menu choose Run then type in
“MSCONFIG” (for Windows Vista users, find the Run command line from Start à All
Programs à Accessories
à Run). From the
window that appears, choose the Startup tab,
and then unselect any programs that do not need to be enabled during computer
start up.
Most computers come installed with a program that
allows a user to scan the hard disk for faults and even repair them if
possible. On many Windows computers
there is a program called Scandisk, found in Start à All Programs à Accessories à System Tools à Scandisk. Another
option is to run a program called Chkdsk, available on all Windows
computers. To run Chkdsk, go to Start à My Computer and
then right click on the image for the C: drive.
Select Properties and then
click on the Tools tab. Under Error Checking, click Check Now. The computer may require the check to happen
while restarting the computer and if so will schedule this task to occur.
5.1.5.
Malware
Viruses, worms, spyware and adware are collectively
known as malware. These undesirable
programs, which are usually added without a user’s knowledge, can significantly
slow down the performance of a computer.
Keeping antivirus software up to date and running scans on a regular
basis are the best ways to prevent virus infections. This is discussed further in section
3.3. Occasionally, however, a computer
will still become infected with a virus or other bit of malware that the
anti-virus program did not catch. Some
signs of these infections, other than slow speed, could be strange files
popping up in folders, new small programs that appear (with an .exe file
extension) or odd performance issues.
When this occurs, the computer lab manager can do an Internet search
using the names of the strange files or programs, or a description of other
symptoms. These searches will often
result in information about the particular malware infection and how to remove it. Another option for computer lab manager is to
try scanning the computer with a second anti-virus program, which might
identify the infection that the other anti-virus software missed. However, the lab manager needs to be aware of
the possibility that the two anti-virus programs will conflict with each other
and themselves cause the computer to run poorly. If a second anti-virus program is installed,
the computer lab manager should make sure that it is not also set up to do any
sort of automatic scanning.
5.1.6.
Overheating
Excessive heat can cause a significant decrease in computer
performance. In order to cool down an
overheated computer processor, the first step to take is to try to cool the
environment around the computer. Avoid
operating the computer if the case is in an enclosed space (such as a drawer or
cupboard). Also try to cool the room
with fans or air-conditioning. The next
step is to verify that all of the fans in the computer case are functioning
properly. Check around the computer
vents to see if the spinning of the fans can be observed or if airflow can be
detected. If neither of these steps
address the problem, the computer lab manager could consider installing
additional fans or replacing the existing fans with higher quality ones.
If none of the measures discussed above have resulted
in improved performance, it’s possible that a computer does not have sufficient
RAM to perform the desired functions.
This problem is most likely if the computer is rather old and has had a
newer (and more memory demanding) operating system installed. For example, a computer with only 256 MB of
RAM would operate slowly with Windows XP, and would not be able to operate
Windows Vista. One option to address
this problem is to install a less demanding operating system. The lightweight open source operating system
Xubuntu, for example, only requires 192 MB of RAM.
Another option is to add more RAM to the
computer. Before taking this step, the
computer lab manager would need to find out the answers to the following
questions:
·
How much RAM does
the computer already have? (This information is available from right clicking
on My Computer from the Start menu.)
·
What kind of RAM
does the computer take? And how much RAM can be added to the computer? The answers to these questions are going to
depend on the number of memory slots available, and the capacity of the type of
RAM that is compatible with the computer.
The best way to find the answers to these questions is via an Internet
search using the brand and model of the computer, “memory” and “upgrade” as
search terms, or by visiting the website for an online RAM sales company (see section 5.7.3).
This should result in the necessary information to make sure that the
right kind of memory is purchased (such as size and type – for example is it
SDRAM or DDR2 SDRAM?). It will also be important to note whether or not the
memory needs to be installed in pairs or if a single strip of RAM will suffice.
·
Does the computer
have enough slots to add in the desired memory?
It is possible that a computer will already have all of the memory slots
filled (for example, there are only two slots and each is already filled with
128 MB RAM strips). In this case, it
would not be possible to upgrade to 512 MB of RAM by adding a single strip of
256 MB RAM. The lab manager instead
would need to purchase two 256 MB strips of RAM, and take out both of the 128
MB strips.
The actual replacement of RAM will be discussed in section 5.7.3 of this module.
There are some computer problems that are common
enough that is helpful for a computer lab manager to have some standard steps
that he or she can follow in case this sort of problem occurs. Below
are the stepwise guides for addressing some standard problems.
5.2.1. The Computer Freezes
It is
relatively common for a computer to freeze.
When a computer “freezes” it might look like everything on the screen has
gone still, or the computer may no longer responding to the inputs (such as
mouse clicks) of the user. It is also
possible that a single program will freeze while the rest of the computer
remains functional. These problems are not something to panic over, since often
they are not a sign of a major hardware problem but instead a sign of a small
glitch that can be easily fixed by restarting a program or the computer. The tip box here shows some simple steps
that the computer lab manager can follow.
It can be very frustrating to have a computer that is
totally “dead”. It’s not working at all
and the user doesn’t know the cause. This
tip
box includes some steps to take to identify and address some common
causes.
Often when there is a problem with a computer’s
hardware or software, the computer will show an error message that explains
what the problem is. The computer lab
manager should make sure that he or she reads these error messages and takes
the information within them into account.
Below are some common error message categories and steps that can be
taken to address the problems.
5.3.1. Out of Memory Errors
Out of memory error messages can be caused by a
variety of problems, including memory glitches (that will be solved by
rebooting), insufficient memory, poor memory management, not enough hard disk
space, faulty memory and software problems.
The user may be running too many programs at once, and could try closing
some of the open programs. If this
doesn’t work, the next step to try is to reboot the computer and see if that
fixes the problem. If it does not, the
following approaches could be considered:
1.
Create more space
on the hard drive by deleting unnecessary files and then defragmenting.
2.
Investigate any
recently added software. Does the
computer system have enough RAM to run this software? Are there any updates or patches for this
software available on the Internet?
3.
Is some memory
management software running? If so,
disable it and see if performance improves.
4.
There may be a
physical problem with the memory or its connection to the motherboard. Try reseating (removing and replacing) the
RAM and if that does not work swapping the RAM (see section
5.7.3) with the RAM from a working computer.
5.3.2. Memory Parity Errors
The term parity has to do with two items matching in
terms of size, type or operation. A
problem with memory parity could be caused by conflicts between two memory
(RAM) strips that are of different brands or types. The error could just be a random occurrence,
however, so it is best to try to reboot the computer first. If this does not help, the following
approaches could be attempted:
1.
Remove any recently
installed RAM (see section 5.7.3) to see if it is
causing the issue.
2.
Try a different
power outlet or power strip, because a poor power supply could also cause this
error.
3.
There may be a
physical problem with the memory or its connection to the motherboard. Try reseating the RAM and if that does not
work swapping the RAM with the RAM from a working computer.
4.
There may be a
problem with the motherboard. Consider
replacing the motherboard.
5.3.3. “The Blue Screen of Death”
“The Blue Screen of Death” is the
colloquial name given to the error code that occurs with Windows operating
systems when a critical error has occurred that causes the system to shut down
to prevent further errors. Its nickname
comes from the fact that the screen turns blue in color, and the computer
“dies” or “crashes”, meaning it is shut down.
These errors are often caused by poorly functioning device drivers,
hardware problems (such as with memory, power supplies or system overheating),
or problems with the system software. Some
suggestions for managing the Blue Screen of Death are shown in the tip
box here.
It is very important that a computer lab manager not
“give up” easily when presented with a computer problem. Instead the computer lab manager should turn
the problem into an opportunity to gain knowledge about computers. This includes asking for help and searching
for information about the particular problem, its causes and solutions. The first step in this process is to see what
advice is available on the computer itself (or another one running the same
operating system). With Windows
computers, there are “Help and Support” documents located on the computer, and
more available on the Internet. From the
Start menu, click on Help and Support and then see which
categories of help best match the problem.
If a computer lab manager doesn’t find the needed
answers using Help and Support on the computer, the next step is to find
answers on the Internet. In most cases,
the computer problems that a lab manager encounters will not be new or
unique. Someone else would have had the
same problem and would have written a description of how they solved the
problem. It is important that the
computer lab manager give very specific search terms and try different terms if
not successful at first. For example, if
a lab manager is having problems getting the sound to work on a specific
computer, “sound problems” would not be a specific enough search. The lab manager would be better trying “sound
problem Dell D600” or “sound failure Dell D600”. If the lab manager knows that the problem is
due to the device driver, an even better search would be “sound device driver
problem Dell D600”.
It isn’t
always easy to know the source of a computer problem, but determining whether
the problem is with hardware or software will help give a computer lab manager
some direction for action in troubleshooting and repair. Some general guidelines for distinguishing
between hardware problems and software problems are in the tip box here, but one
general bit of advice is important for all computer troubleshooters: think about what was happening just before
the problem occurred. If new software
was just installed, it is quite likely that the problem is caused by that new
software. If a power surge occurred, it
is possible that hardware problems were caused by that power surge.
5.6.1. Using Safe Mode
Safe Mode is a convenient tool for both
troubleshooting and repairing software problems. It is a simplified version of a Windows
operating system, which can often be used when a computer is having problems
that prevent its standard Windows operating system from loading. To boot a computer in Safe Mode the user
should turn on the computer and immediately start tapping the F8 key. After a few moments, the Windows Advanced
Options menu will appear. Using the
arrow keys, the user can select Safe Mode and then click Enter to proceed.
Once a computer has been started in Safe Mode, it is
possible to access the diagnostic tools such as Chkdsk (described in section 5.1.4).
Other options at this point include running virus scans, uninstalling
suspicious software, or using System Restore (see section
5.6.4).
If a computer user has identified that there is a
problem with a particular piece of software, before uninstalling that software
it is wise to see if the software producers have identified and fixed any
problems with that software. In many
cases this can be done easily by selecting the “Check for Updates” command in
the software, often found in the Help
menu. Updates are groups of software
patches (small fixes to the software’s program) that address problems that were
found after the software was released, or provide improvements to the
software. If there are any updates
available, these should be downloaded and installed. In many cases the computer (or at least the
particular software program being updated) will need to be restarted after
installation.
If a
particular piece of software does not have a “Check for Updates” option, the
user will need to go to the website for that software and search there for
updates. This can also be used to search
for individual software patches to address the particular problem that the user
has found. It is also possible to do
general web searches on a particular software problem and find patches that
have been produced by individuals or organizations other than those that
produced the software. This can result
in good fixes, but can also introduce other problems into a computer system
(such as other unforeseen software conflicts or malware). A computer lab manager should proceed very
cautiously down this path, if at all.
5.6.3. Reinstalling Software
If updates and patches haven’t fixed the problem with
a particular piece of software, reinstalling that software is a good step to
try next. This will solve problems
caused by the corruption of software (damage to the programs) that can be
caused by malware. It’s important to
properly uninstall all software before reinstalling it. More information on uninstalling and reinstalling
software is found in section 4.4 of this module. Reinstalling an operating system is also an
option (see section 4.3), but the computer lab manager
should make sure that all computer data has been backed up before taking this
action.
System Restore is a utility program that is found with
most versions of the Microsoft Windows operating system. It periodically (when major software changes
are made or at scheduled times) takes images of the computer’s operating system
and other software. These images, called
restore points, are saved so that the user can “reset” the computer system to
that restore point and thus avoid problems that were caused by later
changes. If a computer is reset to an
earlier restore point, however, any software (whether it was problematic or
not) that was installed after the restore point will be uninstalled. To access the System Restore utility on a
Windows computer, go to Start à All Programs à Accessories à System Tools à System Restore.
5.6.5.
Booting from a Different Device
During typical use a computer boots (starts) from
information and instructions that are in its internal hard drive. A computer can also be booted, however, from
other devices such as floppy disks, CD/DVD disks, flash drives or external hard
drives. Booting from these devices is
the only option if the software on the hard drive has been corrupted to the
point that it will not start the computer.
The standard boot order for a computer (the order in which the computer
looks for startup files) starts with the floppy drive (for older computers),
then is followed by the CD or DVD drives and then the internal hard drive. This means that any time the computer starts
up it will first read any disk in the floppy drive to see if startup files are
contained there, and then moves on to the CD/DVD drive if startup files are not
found. This order can be changed by
following the steps in the tip box in section 4.3 of this
module.
In order to boot from a disk, the computer user must
have a boot disk or recovery disk for that computer. Boot disks contain only critical startup
files, and they are best prepared and used by experienced computer technicians. They can also be used as a part of the
reimaging process, described below.
Recovery disks used to come standard with all new computers. In recent years, however, the computer
manufacturers have instead set up systems for users to create their own
recovery disks when first using a new computer.
If a computer lab manager has recently received new computers, he or she
would be wise to create recovery disks before putting the computers into
general use.
5.6.6.
Reimaging Computers
One very handy “tool” for a computer lab manager to
have for managing software problems is disk reimaging (also known as
cloning). The idea here is that a lab
manager can create a complete copy of a computer’s system when it is running
perfectly. These copies, which are known
as images or clones, include all software and files. The purpose of having these images is that
when a computer in the computer lab fails due to a software problem, the
computer lab manager can choose to reimage or clone the computer using the
perfect image, rather than uninstalling and reinstalling each software program
separately until the problem is identified and fixed. One type of proprietary reimaging software is
called Symantec Ghost (see www.ghost.com). A common open source reimaging program is
called Clonezilla (see www.clonezilla.org).
Before creating an image, the computer lab manager
should make sure that the computer is set up “perfectly” and free of any
malware. Images are best made when a
computer is newly setup, before it has seen much use. However the lab manager should make sure that
the computer that is being used to create the image has already been loaded
with all the utilities,
productivity software and educational materials that are commonly used in that computer
lab. The tip box here suggests
some items. The computer lab manager
should also make sure that all of the programs have been updated fully, as
discussed in section 5.6.2 of this module.
Before creating an image, a computer lab manager needs
to consider two questions: 1. What drive should be used to boot the computer
from while creating the image and reimaging a computer? And 2. What media will be used to store the
computer image? The answers to these
questions will depend on the imaging program being used and the limitations of
the computer system. When using
Clonezilla Live, for example, the program can be downloaded from the Internet
to fit onto a bootable CD ROM disk.
Therefore one option is to boot the computers from the Clonezilla Live
CD. The image that is created then can
be easily stored on a flash drive or external hard drive, using the USB port. For complete instructions on using Clonezilla
Live, please see the www.clonezilla.org
website.
Once an image has been created, it can be stored until
needed to reimage the computer it was created from or any other computer with
identical hardware. This is very useful
for a computer lab that received a donation of ten identical computers, for
example. If using the image to reimage
another computer in a computer lab, however, there are some important points
that the computer lab manager needs to keep in mind. The first is computer identity. Any cloned computers will have the same name
and Security Identification (SID). The
computer lab manager should change the name of the computer after reimaging by
right clicking on the Computer (or
My Computer) icon or menu item and
then selecting Properties. The computer SID can remain unchanged.
The second important point is that the software
license keys will be the same for all cloned computers. If the computers are running proprietary
software, the computer lab manager needs to be aware of how many computers are
permitted to run on a single license. If
a license is only for an individual computer, the computer lab manager will
need to buy additional license keys for the software in question and enter the proper
license keys into the computer.
5.7.1.
Tools and Safe Repair Practices
What tools will a computer lab manager need to perform
basic hardware repair? This will depend
on the type of computers being worked on, and also on what tools are locally
available. However, good quality
screwdrivers in different sizes will be on every lab’s equipment list. The majority of the screws encountered in
computers are of the Phillips type (the screw head has an X shape on the top),
but flat head and hex head screws may also occur. A computer lab manager can look and see what
types of screws are in use in the lab before making a purchase. Magnetic tip screwdrivers can be very useful
since the screws will stay magnetically attached to the screwdriver while the
lab manager locates the screw hole.
However it is very important to avoid touching the tips of magnetic
screwdrivers to RAM or hard drives, since the magnetic storage on those devices
could be damaged. A pair of needle nose
pliers may also be useful to assist when working in narrow spaces.
For cleaning computer parts, a computer lab manager
will need some method for blowing dust out of computer hardware. If an electric blower is available, this is a
very good option. Otherwise a hand operated
blower (with a bellows or bladder attached to a narrow outlet) will do. If affordable, a computer lab manager can
also purchase compressed air in aerosol cans.
For dusting and cleaning computer and monitor cases, a lint free cloth
is best. Screens (LCD and CRT) can be
cleaned with slightly damp cloths or with small amounts of mild cleaning
solutions that have been reported to be safe for computer monitors. If RAM
needs to be cleaned, isopropyl alcohol and lint free swaps can be used.
There are several safety concerns (both for the lab manager
and for the computer equipment) that need to be attended to. They are listed below.
·
Working Environment. The computer work room should
be clean, well organized and properly lit.
Avoid hazards to the computer (such as dust or moisture) and hazards to
the workers (such as electrical cords that can be tripped over). The lab manager should also consider good
organization as a way to make repair work more efficient. It should be easy for a worker to return to a
project without any difficulty finding the parts involved.
·
Static Electricity. Static electricity discharges (sparks) can be significantly damaging
to computer equipment such as RAM, CPUs and motherboards. Therefore it is important for the computer
lab manager to ground him or herself before working with computer
equipment. The tip box here gives some
suggestions. If electrostatic mats or
grounding wrist straps are available locally, these items can also be used to
prevent electrostatic shocks.
·
Electrical Shock. Before opening up the case of a
computer or any other electronic device or cleaning it with any fluid, make
sure that it is unplugged. Otherwise,
electricity can be transmitted through the electronic device and into the
worker’s body. This can cause severe
injury or even death. Laptop batteries
should also be removed before performing any laptop computer repairs. It is best to avoid attempting repairs on
computer monitors, particularly CRT monitors due to a risk of a dangerous
electrical discharge.
5.7.2.
Hardware Repair Planning and Strategy
Before beginning a computer hardware repair, it is
important to make sure that the repair is necessary and that a repair plan is
in place. To determine if a repair is
necessary, the lab manager should have worked through the troubleshooting steps
described earlier in this module. If a
computer is still operational, the lab manager should be using software tools
to diagnose (and in some cases repair) problems before physically opening the
computer. For example, the Device
Manager (described in section 5.5) can be used to check
for hardware faults, and a hard drive diagnostic tool (such as Chkdsk,
described in section 5.1.4) can be used to determine if
a hard drive needs to be replaced. Also remember
that error messages can give important information about what is wrong with a
computer.
When developing a repair plan, the computer lab
manager needs to know which parts are going to be replaced and how to find and
remove those parts from the computer. It
is also important to have replacement parts on hand that are known to be in
good condition.
Part re-seating and part swapping are both good
strategies to keep in mind when repairing computers. Re-seating means removing or disconnecting a
part, cleaning it if appropriate, and correctly replacing the part. Sometimes a computer part can function poorly
just because a connection is loose or dirty, and re-seating will improve its
performance. If this does not solve a
problem, a good next step is to try to swap the same part with one from a
functioning computer. This can be a
useful part of troubleshooting, since it helps the lab manager identify whether
or not that part truly is the source of a computer problem, before a purchase
is made. People who are just learning
about computer repair can easily practice this with peripheral devices. If a desktop computer keyboard appears not to
be working, for example, try replacing it with a keyboard that is known to work
properly.
Below are descriptions of some of the most common
hardware repairs, including key steps in the process. In all cases, however, the lab manager who is
just beginning to work on computer repair would be encouraged to complete these
repairs alongside a more experienced technician as they gain skill and
confidence. If the lab manager has an
opportunity (through this course or any other) to attend a hardware repair
training session, he or she should insist on being involved in as much hands-on
training as is possible.
Replacing a Power Supply. For desktop computers in developing
countries, power supply failure is a common problem. This is due to an uneven or “dirty” voltage
and power surges. Before replacing a
power supply, a lab manager should make sure that it truly is dead by following
the tip box in section 5.2.2. Then follow the steps below:
1.
Unplug the power
cord from the back of the computer case.
2.
Open up the
computer case. The method varies with
the brand and model of computer, but often involves laying the case on its side
and opening up the side panel. Some
computer cases use screws and others have buttons to press that release one
side panel.
3.
Find and unscrew all of the screws attaching the power
supply to the back of the case. Usually
there will be four screws, located just outside the cut out in the case (or
along the mesh grid) where the power supply is found. Do not disconnect the various cables
yet. Move the dead power supply as far
out of the way as the cables will allow.
You may be able to set the power supply on top of the case (see photo).
4.
Install the new
power supply and screw in all screws.
5.
One by one,
detach the cables from the old power supply to the various computer components,
and replace them with the cables from the new power supply. Doing this one by one will help make sure
that no components are missed. There
will be power supply connectors for the motherboard and all drives. When removing the cables, keep an eye out for
latches that need to be depressed to release the connector. All of the connectors should only fit in one
direction, and with little force. If a
connector does not attach easily, make sure that it is properly aligned before
pushing harder.
Replacing a
Hard Drive. Replacing a faulty hard drive is not a
difficult task, but a lab manager should have done some investigative work
first to determine if the hard drive is faulty.
This could include running the Chkdsk utility, as described in section 5.1.4, listening for unusual noises coming from
the hard drive and also checking to make sure the cables to the hard drive are
still fully connected. The computer may
also present error codes during start up that indicate a problem with the hard
drive. Before replacing a hard drive, it
is worth trying to reset the BIOS to the default settings to see if this fixes
the problem. To do this, enter the BIOS
during computer start up (as described in section 4.3)
and choose the default settings. Then save
the new settings and exit. The onscreen
instructions in the BIOS program will guide the computer lab manager through
these steps.
Once it has been determined that a hard drive problem
is likely, the computer lab manager should follow the steps below to replace
the hard drive with a known working hard drive.
1.
Disconnect the computer case from electricity and then
open the computer case (as described above).
2.
Locate the hard
drive. It will likely be found in a
metal case or cage near the front of the computer case, below the other
drives. It could be mounted directly on
the cage or it could be mounted on rails that will slide out of the case (see
photo).
3.
Unscrew the hard
drive from the cage or slide the rails out and unscrew the hard drive from the
rails.
4.
Remove the long
ribbon cable from hard drive. There may
have been a small amount of glue used to hold the ribbon in place that will
also need to be removed. Then remove the
smaller power cable. If it is difficult
to remove, gently wiggle the connector back and forth along its long axis as
you pull. Note the orientation of the
connector (which end is the red wire on?) to make sure that the new hard drive
is connected in the same manner.
5.
If there are two
hard drives in a computer, one is called the master and the other the slave. On older hard drives, an electrical
connection needs to be changed to indicate whether the hard drive is a master
or a slave. If the hard drive being
installed has not been used before, it will be correctly set as a master (or
also on the acceptable “Cable Select” setting, used when the ribbon cable has
two connectors – one for a master and one for a slave). If the hard drive has been previously used as
a slave, however, it will need to be changed to a master. To do this, look for a diagram on the hard
drive that shows the pattern for connecting (jumping) two of the eight pins
located between the two cable connectors on the front end of the hard
drive. Then using needle nose pliers,
pull off the jumper that is connecting two of the pins and replace it to
connect the proper pair.
6.
Connect the
cables to the new hard drive. Then screw
the hard drive back on to the rails and slide the rails into position (or screw
the hard drive directly to the cage if there are no rails). Make sure that all of the other ribbons and
cables are as they were found. Close the
case and the repair is complete. Note
that if any new noises or problems appear after the installation, it is
possible that another device or cable was disrupted during the repair and needs
to be reattached or reseated.
Replacing a
Hard Drive for a Laptop Computer. Hard drives for many laptop computers can be
replaced quite easily because the manufacturers have made the hard drives
accessible from hatches on the underside of the computer. To replace the hard drive on a laptop with an
accessible hard drive follow the steps below:
1.
Remove the laptop battery before making this (or any
other) laptop repair. This is important
in order to avoid electricity from the battery flowing through the computer
during repair, which could be damaging to computer components. The technique for removing the battery
depends on the make and model of the laptop, but often involves unlocking the
battery at one or two points (on the underside of the computer) and then
sliding it out.
2.
With the laptop
resting upside down on a table, find the hard drive compartment and unscrew the
screw or screws holding the lid in place.
Remove the lid and examine how the hard drive is attached to the
computer. Most likely you will see that
the hard drive is attached to a cage or brackets that will slide out with the
hard drive (see photo).
3.
Slide out the
assembly containing the hard drive in its cage or brackets. You may have to push the assembly in or lift
it up first in order to clear anything else used to hold the assembly in place.
4.
Remove any screws
attaching the laptop to its cage/brackets, remove the damaged hard drive,
replace it with a functioning laptop hard drive and then retighten all screws.
5.
Slide the
assembly back into the laptop and secure it as it was previously. Make sure
that you push hard enough to reattach the hard drive to the power and data
connectors. Push horizontally (or as
close as possible to horizontally) when reconnecting.
6.
Close the hard
drive compartment and replace all screws.
Then replace the laptop battery, turn the computer over and restart it.
Replacing
RAM.
As discussed in section 5.1.7, a lab manager may
want to add RAM to speed up a slow computer.
RAM also can fail or come loose from its housing and need to be
reseated. If a lab manager has decided
that a computer needs new or additional RAM, it is important to make sure that
the RAM used is compatible with the computer system. There are several online RAM sales companies that
will identify the appropriate RAM if a user inputs the computer make and
model. Two example companies are Corsair
(www.corsairmemory.com) and Crucial
(www.crucial.com). Once
the RAM has been obtained, the lab manager should follow the steps below to
replace the RAM. Please Note: RAM is very
easily damaged by electrostatic charges, so it is very important for the user
to be grounded before picking up RAM.
Also RAM should only be handled by the edges.
1.
Open the computer case as previously described. Find the RAM slots (long parallel connectors).
Note which slots are occupied and if the slots are numbered (at the ends). If the slots are not numbered, the slots
closest to the processor are probably the lower numbered slots and should be
filled first.
2.
Simultaneously
push down and out on both retaining clips (on each end) of a RAM slot to remove
the old RAM. Note the orientation of the RAM so that the replacement RAM can be
put in facing the same direction. There
should be some notches on the bottom edge of the RAM that can be used as a
guide.
3.
Gently place the
new RAM in the socket and press down firmly on the top of the RAM at both ends
(see photo). When the RAM module is
correctly seated, the retaining clips will automatically close.
4.
Close the
computer case as previously described.
Replacing
Laptop RAM. Laptop computers have a compartment on the
back side designed for accessing RAM.
When the screws for this compartment are removed (but don’t forget to
remove the laptop battery first for safety reasons!), the RAM should be
visible. For some laptops, however, only
the slot for expansion (extra) RAM is visible.
In these cases the rest of the RAM is can be accessed by removing the
keyboard, a more difficult task (discussed below). Laptop RAM rests horizontally, with the slot
on one end. To install RAM, hold the RAM
by its edges, and bring it up towards its slot at about a 30 degree angle (see
photo). Then gently push the RAM in
while flattening out the angle.
Other Laptop
Repairs. It is possible to replace the keyboard, individual
keys or the screen on a laptop with only a moderate amount of difficulty. The challenge, however, is that every
different model of laptop requires a different method for accessing and
removing these parts. Either a lab
manager should watch other people do these repairs and learn from them, or find
information on the Internet for the specific desired repair. Specific searches should result in detailed
diagrams, descriptions or videos. For
example, if someone wanted to replace a key on a Dell laptop, the search terms
“replacing laptop keys Dell” will yield useful results. Similarly, if someone wanted to replace the
entire keyboard on a Toshiba laptop, the search terms “replacing laptop
keyboard Toshiba” will suffice. In
general when performing laptop repairs, the computer lab manager should
remember these guiding principles:
1.
Always remove the
battery first for safety reasons.
2.
Keep note of what
screws are removed and in what order.
Also keep track of the actual screws!
3.
When taking a
laptop apart, be slow and mindful of the process. This will make it easier to
put the computer back together afterwards.
For complicated repairs, consider keeping notes of the steps performed.
Problems with a printer are generally in the following
categories:
1.
Software problems
with the computer, including problems with the printer driver
2.
Poor connections
or electrical problems with the printer
3.
Insufficient ink
4.
Paper jam
5.
Printer hardware
problems
All of these except for number five are easily managed
by a trained computer lab manager. The tip
box here gives some suggestions for troubleshooting a faulty printer.
In concluding this module, it is important to
recognize that not all computer problems can or should be fixed. Sometimes computers become too old or
obsolete to make the effort of repairing them worthwhile, and some repairs
(such as repairs to CRT computer monitors) are not advisable except by
experts. Due to these realities,
computer labs often have a collection of old and broken computers and
peripheral equipment that develops and increases over the years. This equipment is collectively known as electronic
waste or e-waste. In many developing
countries e-waste is a problem because the equipment can contain hazardous
materials and there often are not recycling or waste facilities that are
capable of managing these hazardous materials properly.
The first step in managing e-waste is to try to reduce
the amount of it that is produced by a computer lab. A lab manager can do this by avoiding
accepting donations of equipment that is already very old or obsolete, since
this equipment will not remain useful for long.
A lab manager can also make sure that existing equipment is maintained
well so that it remains useful for a longer period of time. The computer lab manager should also work
with any organizations donating computers to discuss the e-waste problem and
strategize how the computers will be disposed of properly when they are no
longer useful.
Options for proper disposal of e-waste will vary from
country to country. In some countries there
will be private companies that collect e-waste, and in others there will be
government projects for e-waste disposal.
Larger non-profit organizations that donate used computer equipment
often have plans for collecting and managing e-waste. If no e-waste options exist in a particular
country, several computer projects could team together to ship a container of
e-waste to an e-waste facility in a neighboring country. One e-waste management facility that accepts
shipments is Desco Electronic Recyclers in South Africa (www.desco.co.za).
5.10.1. Compare the start up speed between two computers, by
actually starting them both up and noting the time it takes for the desktop to
be fully loaded. Then compare the
factors that can control the start up time for each computer. Which computer has more programs that load on
start up (see section 5.1.3)? Which computer has more
RAM? What is the processor speed of each computer? What operating system does
each computer use? Summarize your
findings.
5.10.2. Update the operating system and productivity (office)
software for a computer. Describe the
process you used in each case.
5.10.3. Practice running a disk defragmenter and disk cleanup program
on a computer. Note any change in
performance from before and after defragmentation.
5.10.4. Practice finding help and support on a computer use or
troubleshooting topic, both on a computer and online. Choose a computer topic of interest to
you. If you do not have a topic in mind,
here are some examples: installing a printer, changing the size of desktop
icons, using a text reader (text to voice tool), or taking a screen shot (a
picture of what is on your desktop screen).
Remember to be as specific as possible in your word choice. If at first you are not successful, try other
related words.
5.10.5. Practice using diagnostic tools on a computer. For computers running Windows operating
systems, try Chkdsk (described in section 5.1.4) and the
Device Manager (described in section 5.5).
5.10.6. Investigate a laptop computer. Figure out how to replace and remove the
battery. Also identify all ports and the
access panels for the hard drive and memory.
5.10.7. Observe a computer repair technician in action. Notice what techniques he or she uses to
avoid electrostatic shocks and to clean computer components. Observe at least one software repair and one
hardware repair from start to finish.
Take notes on these procedures for future use.
5.10.8. Practice properly uninstalling and reinstalling a
software program. Choose something that
you have a current installer file for.
5.10.9. Practice starting a computer in Safe Mode. Take note of which features of your computer
function in Safe Mode and which have been disabled.
5.10.10.
Workshop
Activity: As a team, set up a computer “perfectly” so that it is ready to
produce an image or clone. Then
participate in the process of preparing an image and using it to reimage
another computer.
5.10.11.
Workshop
Activity: Practice troubleshooting malfunctioning computers. The instructor may intentionally produce malfunctions
in computers in order to provide you with practice
5.10.12.
Workshop Activity:
Replace the hard drive in a desk top computer.
5.10.13.
Workshop
Activity: Take apart a laptop computer, including accessing all RAM, the
keyboard and screen. Then put the laptop
back together!
6.1.Revisit and reflect on your own skill level after
having completed this module:
6.1.1.
What skills do
you still feel you need in the categories covered by this module? Make a plan for gaining those skills and (if
appropriate) discuss the plan with your supervisor.
6.1.2.
What skills do
you still feel you need in the self-study areas (English reading/writing, touch
typing and computer user skills) presented at the beginning of this
module? Make a plan for gaining those
skills and (if appropriate) discuss it with your supervisor.
6.1.3.
Consider the
topics covered in Modules 2, 3, and 4 of this course (as described in the
introduction to this module). Do you
think that taking those courses (or studying the learning materials for those
courses independently) will help you meet your career goals? Discuss this with your instructor and your
supervisor (if appropriate) and consider your next steps.
6.2.If you work in a project that uses Microsoft or other types
of proprietary software, consider making a shift over to an entirely open source
environment. What would the benefits and
drawbacks of such a shift be? Make a
list of all the FOSS software you would need, including the names of specific
programs if possible. Also what training
would need to occur if you made this switch?
6.3.Workshop Activity:
Participate in a team project to overhaul an old computer. Clean the components, add RAM to the
computer, install an appropriate operating system and install all other
necessary software.
6.4.Workshop Activity: Participate in a workshop
evaluation process.
The table below provides a list of
the Internet resources previously mentioned in this document. The resources are listed in the order they
appeared in this module.
Title
|
Web Address (URL)
|
TypingTest.Com
|
|
Rapid Typing
|
|
Alison (free online courses)
|
|
Sense-Lang.org
|
|
TypeOnline.co.uk
|
|
Good Typing
|
|
European/International Computer
Driving License
|
|
Busuu.com (language training)
|
|
English Online
|
|
Goodwill Community Foundation (free
courses)
|
|
BBC World Service Learning English
|
|
Activities for ESL Students
|
|
UsingEnglish.com
|
|
EnglishLearner.com
|
|
EnglishCafe.com
|
|
Source Forge
|
|
Official Ubuntu Documentation
|
|
Microsoft Downloads
|
|
AVG Free Antivirus
|
|
Avast Antivirus
|
|
Malwarebytes’ Anti-Malware
|
|
Microsoft Community MAR Program
|
|
CNET Download.com
|
|
Symantec Ghost
|
|
Clonezilla
|
|
Foner Books – Replacing PC Parts
|
|
Corsair Memory
|
|
Crucial (computer memory)
|
|
Desco Electronic Recyclers
|
Bit. (2010). In Wikipedia, The Free Encyclopedia. Retrieved
January 26, 2010, from: http://en.wikipedia.org/w/index.php?title=Bit&oldid=339499368
Blue Screen of Death (2010). In Wikipedia, The Free Encyclopedia. Retrieved January 26, 2010, from:
http://en.wikipedia.org/w/index.php?title=Blue_Screen_of_Death&oldid=336735006
Computer. (2010). In Wikipedia, The Free Encyclopedia. Retrieved January 26, 2010, from: http://en.wikipedia.org/w/index.php?title=Computer&oldid=339667990
Computer Ports (Hardware). (2010). In Wikipedia, The Free Encyclopedia. Retrieved January 26, 2010, from: http://en.wikipedia.org/w/index.php?title=Computer_port_(hardware)&oldid=338140393
Computers for Zambian Schools. (2008). Basic Computer Maintenance and
Troubleshooting. Lusaka, Zambia.
PCTechBytes. (2009). Computer Troubleshooting Zone. Retrieved
January 26, 2010, from PCTechBytes: http://www.pctechbytes.com/troubleshooting/
Rosenthal, M. (2009). Replacing Laptop Hard Drives. Retrieved
January 26, 2010, from Foner Books: http://www.fonerbooks.com/laptop_1.htm
Rosenthal, M. (2008). Replacing PC Parts. Retrieved January 26,
2010, from http://www.fonerbooks.com/replace.htm
Rosenthal, M. (2009). Upgrading Laptop Memory. Retrieved January
26, 2010, from Foner Books: http://www.fonerbooks.com/laptop_2.htm
Yarnold, S. (2008). Upgrading and Fixing a PC, Second Edition.
Warwickshire, United Kingdom: In Easy Steps Limited.
About Zambia Pacific Trust
There are
many challenges for schools and community organizations in Zambia to consider
when starting or maintaining computer projects.
Sourcing good quality computers is just the beginning. The organizations also need to consider
infrastructure issues, staff training, computer education curricula, and
internet connectivity. Zambia Pacific
Trust (ZPT) helps institutions address these challenges through advice,
training, and a cost-sharing grant process.
ZPT currently works with five schools in the Lusaka area, but has plans
to add other organizations in the future.
For more information please contact info@zptrust.org.
About Heidi Neff
Heidi Neff
is a former high school science teacher with 15 years of experience in the
classroom. While teaching in Seattle,
Washington, she used computers extensively as a part of her curriculum. She also assisted with computer training in
Zambian schools as a part of the Seattle Academy Zambia Program. Ms. Neff starting working with ZPT in 2006,
assisting their efforts to support school computer projects in Zambia. She is currently a consultant specializing in
IT in Education. For more information please contact her at heidi.h.heff@gmail.com.
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