COMPUTER BOOTING

For the computer to run it needs an OS, because the OS is the software that manages all the
activities and devices attached to the computer. However, when the computer is off, the OS is
not running, and is simply stored on the hard disk inside the computer. Therefore when a user
presses the power button when the computer is off, the OS cannot get itself out of the hard drive
since is it off. So how does the computer start up without the OS?

DEFINITION OF BOOTING
Booting is defined as the process of starting up a computer. Booting is also the process of
loading the operating system (OS) from disk into working memory. Booting (also known as
booting up) is the initial set of operations that a computer system performs when electrical
power is switched on. The process begins when a computer that has been turned off is re-
energized, and ends when the computer is ready to perform its normal operations.

Steps involved in the booting process

1. The power supply sends a signal to the components in the system unit.
2. The processor finds the ROM chip(s) that contain the
BIOS (Basic input/output system).
3. The BIOS performs the POST (Power-On Self Test) which checks components such as the
mouse, keyboard and adapter cards. A series of messages may display.
4. The results of the POST are compared with data in a CMOS chip.
5. The BIOS looks for system files on the Hard disk (C :)
6. The system files and the kernel of the Operating System load into RAM from the Hard Disk.
7. The OS loads configuration information and displays the welcome screen.
8. On start up, the OS may verify that the person attempting to use the computer is a legitimate
user through use of a password.
9. After the user logs on, the desktop and icons are displayed on the screen.
10. Finally, the operating system also executes programs in the Startup folder, which contains a
list of programs that open automatically when you boot the computer.

Power-On Self-Test (POST)

What does Power-On Self-Test (POST) mean?

A power-on self-test (POST) is a succession of built-in diagnostic tests performed when turning
on a computer. This series of tests determines proper functioning of the following:
1) Random access memory (RAM)
2) Disk drives
3) Hard drives
4) Central processing unit (CPU)
5) All other hardware devices

How is POST executed?

1) The POST is run by a computer's basic input/output system (BIOS).
2) The initial tests, include reading configuration information stored in the complementary
metal-oxide-semiconductor (CMOS) chip.
3) This information is then compared to hardware devices, such as the CPU, hard drive,
disc drives and video card. Then, ROM BIOS assigns system resources as needed.
These set up the environment required by the operating system (OS).

Basic Input/Output System (BIOS)

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What does BIOS mean?
BIOS (basic input/output system) is the program a computer's microprocessor uses to get the
computer system started after you turn it on. It also manages data flow between the computer's
operating system and attached devices such as the hard disk, video adapter, keyboard, mouse,
and printer.

BIOS is a program that is made accessible to the microprocessor on an erasable programmable

read-only memory (EPROM) chip. When you turn on your computer, the microprocessor passes
control to the BIOS program, which is always located at the same place on EPROM.

When BIOS boots up (starts up) your computer, it first determines whether all of the
attachments are in place and operational and then it loads the operating system (or key parts of
it) into your computer's random access memory (RAM) from your hard disk or diskette drive.

The four main functions of a Personal Computer’s BIOS are:

1) POST - Test the computer hardware and make sure no errors exist before loading the
operating system.
2) Bootstrap Loader - Locate the operating system. If a capable operating system is
located, the BIOS will pass control to it.
3) BIOS drivers - Low level drivers that give the computer basic operational control over
your computer's hardware.
4) BIOS or CMOS Setup - Configuration program that allows you to configure hardware
settings including system settings such as computer passwords, time, and date.

CMOS
What is CMOS?
Complementary metal-oxide semiconductor, or CMOS, refers to a battery-powered memory
chip in your computer that stores start-up information. Your computer's basic input/output
system (BIOS) uses this information when starting your computer.

Information stored in CMOS may include:

1) Amount of memory,
2) types of disk drives,
3) keyboard, monitor,
4) current date and time
5) Port settings (parallel and serial)

What is the difference between BIOS and CMOS?

1) The BIOS is a computer chip on the 1) The CMOS is also a computer chip on
motherboard. This chip contains a the motherboard. This is a type of
special program that helps the memory chip which stores information
computer processor interact and about the computer components, as
control the other components in the well as settings for those components.
computer.
2) In order to retain the information in the
2) These other components include disc CMOS chip, a CMOS battery on the
drives, video cards, sound cards, motherboard supplies constant power
network cards, floppy drives, USB to that CMOS chip.
ports, hard drives, and others.
3) If the battery is removed from the
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 3) Without the BIOS, the processor would motherboard or runs out of juice (e.g. a
not know how to interact or interface dead CMOS battery), the CMOS would
with the computer components, and lose the information stored in it.
the computer would not be able to
function.

4) The BIOS program on the BIOS chip

reads information from the CMOS chip
when the computer is starting up,
during the boot up process.

SYSTEM SPECIFICATIONS:

What is a System Specification?

The term System (computer) specification or ‘spec’ is a list of the key components that make up
the computer. It is provided by retailers to help buyers decide which PC and which combination
of features, they need.

When reviewing a computer specification, the most important components to take account of
are the processor, the amount of RAM and the size of the hard drive as these are central to
the overall capability of the system. An example of a System of Personal Computer
Specification is listed below.

▪ Intel or AMD Processor

▪ 2 GB SDRAM
▪ 160GB Hard Drive
▪ 48X Max CD/DVD Drive
▪ 17” Flat Screen Colour Monitor
▪ Integrated Graphics Card
▪ Microsoft Windows XP Pro

Detailed Explanations on Specifications:

Processors
The processor is the ‘brain’ of the computer and controls most of the work done. Two
companies –Intel Incorporation and AMD Incorporation – manufacture most of today’s PC
Processors and both offer a range that balances price and performance. Processors are
generally defined by their speed – in megahertz (MHz) or in gigahertz (GHZ) – and this relates
to the number of operations they can perform per second. The higher the value, the faster the
PC will perform and the more expensive it generally is.

Memory (RAM)
The main working memory in a computer is called random access memory or RAM. The
processor uses this memory to run programs. RAM is measured in megabytes (MB) or
gigabytes (GB). Most modern computers use DDR3 RAM.
▪ A minimum of 2024MB (2GB) of RAM is recommended for general purpose PCs and is
also sufficient for PCs running multimedia applications i.e. those on which digital music,
digital video or high-end graphics are being created or edited.

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Storage – The Hard Drive
The hard drive is a central storage area for the programs being run and the documents or
folders created. The hard drive is the computer’s primary storage area. It stores the applications
and programs that run on the PC, as well as any work created by users. From a school’s
perspective, the capacity of the hard drive, measured in gigabytes (GB) is a key criterion and
should be given due consideration when reviewing PC specifications.
▪ A hard drive capacity of at least 80GB is recommended for general purpose PCs.
▪ A hard drive capacity of 200GB or more is recommended if working with multimedia
applications where large graphics and digital audio/video files are being created and
stored.

Monitors
The older CRTs have been largely replaced by TFT flat-screens. A 15’ TFT has the same
viewing area as the older 17” CRT
▪ Average entry-level PCs usually come with a 17” Flat-screen and this is adequate for most
general purpose applications.
▪ Larger 19” flat screens are available and may be appropriate if video editing and advanced
graphics work is being carried out.
▪ Teachers of students with special needs may want to consider using larger monitors with
their students.

CD/DVD Drives
CD-R/W and DVD-R/RW drives are standard on PCs and allow the information on a compact
disc (either data or audio) to be read and written to by the PC. It is defined by its speed (i.e. 48x
or 48 speed). DVD drives can read both CDs and DVDs These allow you to copy to blank CDs.
52X DVD-RWs are standard on higher performance computers.

Graphics Card
These cards are installed inside a PC and are responsible for determining the quality of the
audio and visuals (graphics and video) output by the computer. They hold their own memory in
MB), which is why they add to a computer’s capability.
▪ An integrated graphics card with 256MB of memory is recommended for general purpose
PCs.
▪ Computers running high-end applications generally require a separate 25MB graphics
card

Sound cards
A sound card generally comes as standard in most PCs purchased today. If students intend to
work extensively with digital music, the school should consider getting a high-end sound card as
this will create a greater depths, complexity and realism of sound.

Speakers and headphones

Most computers come with either built-in or external speakers. Schools may also consider
buying headphones to control sound levels within a classroom or computer room.

Network Interface Card (NIC)

A network Interface Card allows a computer to be connected to a network. It is recommended
that all PCs be purchased with a suitable Network Interface Card (NIC). A 10/100/1000 Mbps
(Mega bits per second) card is the standard network card today. Few school networks currently
operate at speeds higher than 100Mbps.

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Operating Systems (OS)
PCs are generally purchased with an operating system
pre-installed. It is worth checking that your existing
software will still work with the operating system of any
new systems being purchased. At present, Microsoft’s
newer OS is Windows 10. However when ordering
computers schools need to specify a base operating
system. The choice of base operating system should be
made along with their choice of operating system license.
Linux is an open source free operating system which is not
widely used by schools at present moment, though it may
be suitable for schools that are aware of its capabilities.

Factors to Consider before Purchasing a Computer

Consider the following points when purchasing PCs
1. What is the intended use of the PC and will the chosen
specification fulfill these aims?
2. Is the PC compatible with existing computer equipment and
software?
3. Nature of the school e.g. a school for the deaf would need
some hardware for the deaf.
4. Ergonomics and safety provisions for the hardware e.g.
comfort, safety, efficiency etc
5. Cost of hardware components given the available school
budget like installation, initial hardware cost and
maintenance plus repair.
6. After sale services provision such as free maintenance,
warrants/guarantees for a period of time like one year.
7. Source of hardware given the school foundation body and
virtues
8. School and government policy governing procurement laws
and procedures.
9. Data/information security provisions/concerns
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10. Computer hard disk capacity
11. Memory (RAM) capacity
12. Processor speed of the PC.
13. Compatibility with the existing infrastructure in the school
14. Provision for future growth and development (upgradeability)
15. Past experience of working state of the nature of the
computer.
16. Reputation of the supplier
17. Environmental concerns
18. Technical advice and support
19. Space for storage
20. Consider the internal Network Interface Card
21. Consider Resolution for high Graphics
22. Will added peripherals be required such as headphones,
optical mice etc.

SOFTWARE INSTALLATION
Software Installation (or setup) of a computer program is the act
of making the program ready for execution. Because the process
varies for each program and each computer, programs
(including operating systems) often come with an installer.
What is an Installer?
An installation program or installer is a computer program that
installs files, such as applications, drivers, or other software, onto
a computer. Some installers are specifically made to install the
files they contain; other installers are general-purpose and work
by reading the contents of the software package to be installed.

Types of Software Installations

Attended installation
This is an installation process which usually needs a user who
attends it to make choices, such as accepting or declining an end-
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user license agreement (EULA), specifying preferences such as
the installation location, supplying passwords or assisting
in product activation

Silent installation
This is an installation which does not display messages or
windows during its progress. The reason behind a silent
installation may be convenience. Malware is almost always
installed silently.

Unattended installation
This is an installation which is performed without user interaction
during its progress or with no user present at all. One of the
reasons to use this approach is to automate the installation of a
large number of systems. An unattended installation either does
not require the user to supply anything or has received all
necessary input prior to the start of installation.

Headless installation
Installation performed without using a computer
monitor connected. In attended forms of headless installation,
another machine connects to the target machine (for instance, via
a local area network) and takes over the display output.

Scheduled or automated installation

This is an installation process that runs on a preset time or when
a predefined condition transpires, as opposed to an installation
process that starts explicitly on a user's command. For instance,
a system administrator willing to install a later version of a
computer program that is being used can schedule that
installation to occur when that program is not running. An
operating system may automatically install a device driver for a
device that the user connects. Malware may also be installed
automatically.

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Clean installation
A clean installation of an operating system is an installation in
which the target disk partition is erased before installation. This is
in the absence of any interfering elements such as old versions of
the computer program being installed or leftovers from a previous
installation.

Network installation
Network installation, shortened netinstall, is an installation of a
program from a shared network resource that may be done by
installing a minimal system before proceeding to download further
packages over the network. This may simply be a copy of the
original media by software publishers that offer site licenses for
institutional customers, may provide a version intended for
installation over a network.
Installing System Software

Things You'll Need

1. A computer
2. A disk with an operating system
3. Some basic knowledge
4. A working second PC just in case something goes wrong helps

Procedure
1. Decide what you would like to do. Are you going to reinstall
your operating system because of problems, upgrading your
current version, or are you installing an operating system on a
new computer? Make sure that you have the new operating
system install program.
2. Back up your data. If you are reinstalling your operating
system, it is likely that you will need to wipe the disk. Back up
your data before doing so, as everything on the disk will be
destroyed.
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3. Boot up. Turn on your computer and quickly enter the boot
menu. The owner's manual for your computer or motherboard
should have instructions on how to do this. It will show on the
screen for a brief moment too. Select the drive that contains
the setup disk (and be sure you have inserted it). Save the
setting and exit.
4. Start the installation. It may take the install program a few
minutes to load, this is normal. Once it has loaded, follow the
onscreen instructions. If you are installing a new operating
system on a new computer or reinstalling due to a problem,
wipe the disk. Be sure you have saved everything that you
would like to save before starting this process.
5. Sit back and relax. The installer may ask you for some
information while it's installing, but for the most part, just
waiting is okay. Near the end of the installation, the installer will
ask you for last-minute information, like your name, the name
of the computer, sign in name, password, time zone, etc..
6. Enter the product ID. If you are installing a consumer operating
system like Windows, it will probably require you to enter a
product ID. Look at the back of the CD case for the product ID
or, indeed, on the case of the computer if the computer came
with a version of Windows.
7. Reboot. Once you reboot, the computer will finalize everything
and log you in. At this point, you may need to install drivers.
Insert any disks that came with your computer or its parts that
are NOT an operating system, and allow the drivers to be
installed (if necessary).
8. Allow updates. This is especially important in Windows. Allow
the computer to seek updates and install them. Look for a "top
10 things to do" list for that operating system.
9. Install antivirus software. If you are using Windows without
antivirus software while on the web, you are extremely
vulnerable to all kinds of malicious programs. Before you do
anything, even installing Firefox, install antivirus.

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Warnings
1. Be sure to back up everything before you do this, unless you
are upgrading. However, it is wise to back up while upgrading,
too.
2. If you are installing Windows and you go online, be sure to
install antivirus software before you do so.
3. If you are moving from Windows to Linux, and don't know what
you're doing with Linux, perhaps a full install isn't right. If your
computer is new enough to boot to a USB device, install Linux
to a flash drive. Otherwise, just boot from CD to use it.
4. Windows will be unable to read Linux partitions.

Installing application software

After configuring the computer completely, and working well with
an operating system, application programs can now be installed.
The steps followed are:
1. Insert the application CD-ROM into the CD-ROM driver. In
most cases, it will start automatically.
2. Follow the instructions on the screen until the end, filling your
name or that of the organization, product keys where
applicable and restarting the computer.
3. In other instances, you have to open the CD-ROM and browse
for the SETUP.EXE or Install program. Double click on it and
the installation wizard will start. Follow the instructions as
above.

SOFTWARE UPDATING AND UPGRADING

SOFTWARE UPGRADE
A Software Upgrade is to replace a product with a new version of
the same product.

Why Upgrade?
1) Bring systems up to date
2) Improve its characteristics
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3) Support industry regulatory requirements
4) Access emerging technologies
5) Meet demands of changing markets
6) Receive product support
7) Improves computers performance
8) Install new features not available in previous version
9) Better product stability
10) Avoid risks of discontinuity
11) Fix current bugs
12) Improved security

SOFTWARE UPDATE
A software update is a free download for software that provides
fixes for features that are not working well. It adds minor software
enhancements and compatibility. It includes driver updates that
improve operation of hardware or peripherals or adds support for
new models.

Why Update Software?

1) Add new features
2) Remove outdated features
3) Update drivers
4) Fix security holes (security vulnerabilities)
5) Better functionality
6) Delivering bug fixes

Uninstalling software
You can uninstall a program from your computer if you no longer
use it or if you want to free up space on your hard disk. You can
use Programs and Features to uninstall programs or to change
the program's configuration by adding or removing certain
options.
1. Open Programs and Features by clicking the Start button,
clicking Control Panel, clicking Programs, and then clicking
Programs and Features.
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2. Select a program, and then click Uninstall.

Some programs include the option to change or repair the

program in addition to uninstalling it. But many simply offer the
option to uninstall.

To change a program, click Change or Repair. If you are

prompted for an administrator password or confirmation, type the
password or provide confirmation.

Why Uninstall Software

There are several reasons why you may want to uninstall
software from your computer.
1. It could be that the software is no longer being used and is
unnecessary.
2. It conflicts with other programs.
3. It's not functioning as expected.
4. You just want to free up some space on your computer's hard
drive.

COMPUTER TROUBLESHOOTING

Troubleshooting is the process or identifying and fixing

computer problems. Computer troubleshooting may
involve hardware or software and can sometimes involve both
at the same time. The basic process of troubleshooting is to
check the most general possible problems first, and then
gradually check for more specific problems.

Even with the most updated software and hardware,

occasionally computers can malfunction.

In order to solve a problem, you must figure out which part of

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the system is malfunctioning. You will need to check each
component of the computer, unless it is obvious where the
problem is coming from. Isolating the problem will help you
solve the problem quickly.

Backing up your important computer files to another source will

ensure that if your problem cannot be corrected, you will still
have a safe copy of your information.

BASIC TROUBLESHOOTING STEPS

1. Close open programs and windows you are not currently
using.
2. Make sure all of your power cords are connected properly.
3. Try to repeat the sequence of commands you performed
before the problem occurred. See if this causes the same
response by your computer.
4. Press the F1 key to access the Help window. You can
search
for a solution to your problem once the Help window
appears.
5. If there is an error message, record the full message for
future reference.
6. Restart your computer to see if it clears the problem. To
restart your computer, open the start window and select
the Restart button instead of the Log Off button.
7. If restarting the computer does not clear the problem, shut
down the computer and then start it back up again.

COMMON TECHNOLOGY ISSUES

Below we describe some of the most commonly encountered
technology issues and possible solutions to correcting the
problem.

Common Solutions for Technology Issues

A. Issue: The printer is not working.
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 1. Check if the printer is turned on. If not, turn it on and try
again.
2. Check if the printer has paper. If not, put paper in the
paper tray and try printing again.
3. Check if the printer has a paper jam. If so, remove the
paper, close the printer, and try printing again.
4. Ensure that all printer cables are properly connected.
5. Turn off the printer and turn it on again.
6. Check to see if a new printer driver is needed. Do
this by going to the manufacturer’s website to search
for your printer model and checking for any updated
driver. Seek assistance from your system
administrator before installing any drivers.
7. Check your printer’s print queue by looking for the
printer icon in the system tray and double-clicking it.
The print queue shows you the status of each job as
well as the general status of your printer.
8. Ensure that ‘Use Printer Offline’ isn’t checked.
Sometimes, printing while your printer is turned off
can cause Windows to set your printer to work
offline, and that can stall jobs sent later.

B. Issue: The computer is frozen. A program is not

responding.
1. Push the Ctrl, Alt, and Delete keys at the same time.
Then, start the Task Manager, highlight the program’s
name, and hit the End Task button.
2. Perform a hard reboot by simply pressing the on/off
button to turn off the computer manually. This action
should only be done as a last resort if you have an
unresponsive program or critical error. This process
could cause data loss or corruption.
3. Once the computer is responding again, run a virus
check.

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C. Issue: The mouse is not working correctly.
1. Check if the mouse is securely plugged into the computer.
If not, plug it in completely.
2. Check to see if the cord has been damaged. If so, the
mouse may need replacing.
3. If you are using a cordless mouse, try pushing the
connection button on the underside of the mouse to
reestablish a connection.
4. Clean the mouse, especially on the bottom.

D. Issue: The keyboard is not working.

1. Make sure the keyboard is connected to the computer. If
not, connect it to the computer.
2. If you are using a wireless keyboard, try changing the
batteries.
3. If one of the keys on your keyboard gets stuck, turn the
computer off and clean with a damp cloth.
4. Use the mouse to restart the computer.

E. Issue: New hardware or software is working incorrectly.

1. Verify your computer meets the requirements of the
program or utility.
2. Uninstall and install the program.
3. There could be a conflict with another installed program
and you should contact your system administrator
F. Issue: The computer is slow.
1. Restart your computer.
2. Verify that there is at least 200-500 MB of free hard
drive space. To do so, select Start and click on My
Computer or Computer. Then highlight the local C
drive by clicking on it once. Select the Properties
button at the top left-hand corner of the window; this
will display a window showing how much free and
used space you have.
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3. Empty your recycle bin by right-clicking on the
Recycle Bin icon (usually on the desktop), then
selecting Empty Recycle Bin.
4. Check your mail files. Remove any large attachments
and delete unused mail.
5. Images and videos take up a lot of space, so consider
moving those to an external drive.
6. Remove temporary files from the Internet. To do so:
a) Click Start button | My Computer or Computer.
b) Click Open Control Panel at the top of the window.
c) Click Network | Internet |Internet Options.
d) Select the General tab and click Delete under
Browsing History.
9. Perform a disk cleanup. To do so:
a) Click Start button | My Computer or Computer.
b) Highlight the local C drive by clicking on it once.
c) Select the properties button at the top left of the
window.
d) Go to the General tab and select Disk Cleanup.
e) Once the Disk Cleanup finishes running, click on
Clean up System Files; this will delete any
unnecessary system-related files from your local
disk.
10. Information in computer files changes often, resulting
in gaps or spaces within the file. This takes up more
space on the computer and can cause the computer to
slow down. To reclaim these gaps in space, run disk
defragmentation. To do so:
a) Click Start | My Computer or Computer.
b) Highlight the local C drive by clicking on it once.
c) Select the properties button at the top left of the
window.
d) Go to the Tools tab and select Run Defragmentation.
9. Old or unused programs that aren’t being used
may still have components running behind the scenes
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 when you start your computer, which can slow down
the system. You can prevent these programs from
running when you start your computer by removing
unused shortcuts and turning off unused program
services.
10. Remove unused shortcuts from Windows startup
a) Click Start button | Select All Programs | Click
Startup
b) Right-click the shortcuts that you do not use and click
delete
11. Disable unused program services
a. Click Start button | Control Panel | Administrative
Tools | Services
b. For each program/service that you are certain
that you do not need, click on the Service to
highlight it, click the Stop link to stop the service
from running, then double-click the service,
choose Startup Type of Disabled, and click OK.
12. Run a virus scan to remove potential viruses
that can slow down your computer.
E. Issue: The browser’s homepage suddenly changed.
1. This is a common symptom that a virus or
browser hijacker may have infected the
computer.
2. Try re-setting the home page to the default:
a. In Internet Explorer:
i. On the Tools menu, click Internet Options.
ii. Click the General tab.
iii. In the Address box, type the Web address you
want for your home page.
iv. Click OK.
b. In Mozilla Firefox:
i. Open the web site you want to set as your home
page.
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 ii. Click the icon to the left of the web address and
drag it to the Home button.
iii. Click Yes.
3. If the home page still reverts back to the “new” page,
do an Internet search using keywords that include the
name of the “new” homepage and the word “virus.” If
there is a virus, this search may reveal more
information on the virus and how it can be safely
removed.
4. Run a virus scan.
F. Non-system disk error when the computer system is
switched on
1. Eject the disk from the drive press any key on the
keyboard to enable the boot process to continue
2. Restart the computer
3. Check hardware connection
4. Reformat the hard disk
G. Low disk space and computer is slow
1. Fix this by deleting some files using disk cleaner utility
2. Close some files which are open and would occupy the
RAM
3. Back up and delete unnecessary files from computer
4. Use of cloud computing
5. Increase the RAM
6. Defragmenting the hard disk
7. File compression
8. Run anti-virus to scan the device
9. Increase/slave/add new HDD
H. Access denied when a user wants to access a particular
file
1. Exit or stop programs that are running and could be
blocking the users’ tasks from running
2. Install and run the anti-virus
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 3. Adjust users’ settings to allow access
4. Provide password
5. Adjust windows firewall and allow access
I. Out of memory
1. Exit or stop programs that are running and could be
blocking the user’s tasks from running
2. Install or upgrade the RAM by buying another chip and
fixing it on the memory slot of the mother board and
restarting the computer to implement the upgrade.
3. Run a virus scan
4. Restart the system
J. Device not ready
1. Disable particular disk drive from the device manager
2. Give it time to activate
3. Re-install drivers if they are not working properly.
4. Check and change power connection points e.g. USB
5. Restart the device
6. Re-install the Operating system
7. Scan for viruses/malware
8. Uninstall and or deactivate software blocking the
hardware from working such as Deep Freeze.
9. Change ports where applicable
10. Disable and enable the device.

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