Transcript computer management

COMPUTER MANAGEMENT
System start-up
• Before switching on a computer, make sure that all the
components are properly connected.
• The computer must be connected to an active power source
therefore turn on the switch from the mains.
• Switch on the monitor first, then the system unit using their
respective power buttons.
• Notice that when the power is on, the computer
automatically goes through a process of self-test and
preparation for use.
Booting a computer
• Booting refers to the process of loading an operating system
(programs that manage and control the use of hardware and
software on the computer) into a computer’s main memory to
make a computer ready for use.
• Booting is the process of loading the operating system to
memory and readying the computer system for use. .
• Booting is the process of starting-up of a computer, which
involves loading the operating system and other basic
software and readying the computer for use.
Types of booting
•Cold booting
•Warm booting
Cold booting
• Cold booting happens when you turn
on a computer after it has been
powered off completely.
• Cold booting refers to turning on a
computer after it has been off by
loading the operating system.
Warm booting
• Warm booting refers to restarting or resetting a
computer that is already powered on.
• The reset button, Ctrl+Alt+delete key combination
was designed to allow a soft reboot which is quicker
and more convenient.
• Warm booting refers to resetting the computer when
the Operating System is already running by using
reset button or ctrl + Alt + Del.
THE BOOT PROCESS OF A COMPUTER
• Power on reset (POR)-the computer checks
the central processing unit and memory
• Power on self-test (POST)-the computer
checks for all other components connected
to it
• Loading operating system-the computer
looks for the operating system from a floppy
diskette and hard disk.
Power on reset (POR)
• POR is the first stage during the booting
process where a computer checks the
memory and CPU to find out if they are
functioning normally.
• POR happens as soon as a computer is
switched on.
Power on self-test (POST)
• POST is the second stage during the booting process where
the computer checks all the devices connected to it in order
to make sure that the devices are functioning well to enable
the computer to execute the processing of data responsibly.
• In case there is a fault, a message will be displayed on a
screen showing the faulty part; the end of this process is
marked by a beep.
• Incase several important devices are faulty the computer
might stop at this stage.
Loading the operating system
• During this stage of booting, the computer begins to look for
the operating system.
• The computer does this starting with the floppy drive, once a
computer finds no diskette in the floppy drive, it will proceed
to start from the hard disk.
• On getting the operating system, the computer will load it into
the memory (RAM).
• The name of the operating system will then be displayed on
the screen at this stage and after a few seconds the computer
will be ready for use.
Summary of the boot process
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The power supply sends an electrical signal to the motherboard and other
devices located in the system unit.
The CPU resets itself and looks for the ROM that contains the BIOS (basic
input output system) (computer’s startup instructions)
The BIOS executes the power on self test (POST) to make sure that the
computer hardware is connected properly and operating correctly.
The results of the POST are compared with data in a CMOS chip (contains
the computer’s configuration information) on the motherboard.
If the POST is completed successfully, the BIOS looks for the boot program
that loads the operating system.
Once located, the boot program is loaded into memory and executed which
then loads the kernel (core of the operating system) of the operating
system into RAM.
The operating system loads system configuration information and the
remainder of the operating system is loaded into RAM and the desktop and
the icons display on the screen.
Study questions
• Explain the procedure you would follow before you start a
computer.
• Define the term booting as used with reference to computers.
• Differentiate between warm booting and cold booting.
• Suggest any two reasons as to why a computer has to be
restarted.
• Write the abbreviations POR and POST in full.
• Explain the boot process a computer follows when starting.
• Mention any two devices from which a computer can boot.
• Suggest three effects of booting a computer.