Introduction
Starting and turning off Windows computers: Start-up (called boot) is the procedure that loads the operating system. Once the Windows computers system is loaded (and see you see the initial screen of Windows computers), you can run any of the applications you want. Booting an operating system is done automatically by loading a small program that takes over the computer, which uploads the whole operating system, starting it.
Step 1
• After starting the computer, the CPU take control of the computer and executes the instructions received from ROM BIOS who is located in the ROM (Read Only Memory), which is a chip on the motherboard. The BIOS is already available because it is implemented in ROM chip, whose content is not erased when the computer is shut down.
• BIOS performs an initial test to ensure that all hardware is operational (example: computer will not start without its memory).
• The last part of the BIOS instructions contains the boot routine. It is programmed to read the first sector of first hard drive (an area of 512 bytes) where there is an MBR (master boot record) that copies information from this sector in a certain place in RAM (at hex 7C00).
• MBR contains a master boot program and a partition table (partition table) that describes the hard drive partitions. BIOS boot routine executes the master boot program that continues booting. The program reads the master boot disk partition table to determine which primary partition is active.
Step 2
• After identifying the active partition, MBR program launches its boot program.
• In its turn, the boot program uploads the necessary files (core OS) and starts the operating system.
• After all files have been loaded for the operating system, the computer starts operating the system and performs the required initial orders, displaying the log-on window.
• After log-on, Windows computers lunches the Start-up programs (automatically launched with the OS) After all files have been loaded for the operating system, the computer starts operating the system and performs the required initial orders, displaying the log-on window.
• After log-on, Windows computers lunches the Start-up programs (automatically launched with the OS)
Step 3
Entry in Windows XP: For computers connected to the network, or used by several users, at start-up a log-on box will appear. Enter your user name and password. Turn off button allows us to close quickly and the system will shut down.
Step 4
Entry into Safe Mode: Safe Mode is a simplified version of Windows computers, used for debugging. To enter Safe Mode, press F8 at start-up and choose Safe Mode from the context menu, or press the F5 key directly. If you try to remedy a problem, then restart the computer (Start-Shut down- Restart).
Step 5
Changing user to use another Windows computers account:
• Choose Log Off option from the Start menu
• In the Log Off screen, click Log Off.
Log-on screen appears again, then choose another user.
Shutting down Windows XP
Press the Start button, then choose Turn Off Computer option.
• Turn Off (final closing)
• Restart (shutdown, then reboot)
• Hibernate. Sometimes, Hibernate option appears only if you use the SHIFT key.
