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 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.