1. Backup all your data, if possible. (very important!)
2. Know all your hardware and have the drivers ready (ie; modem, video card, sound card, mouse, printer, scanner, etc.)
3. Start your computer and enter your BIOS Setup.
4. Set the computers BIOS to Boot from your CD-R or DVD-R, whatever the case maybe.
5.Put the the Windows Install CD into the CD-R or DVD-R unit, save and exit the Bios Setup and the computer will re-boot.
6. You should see the computer booting from the Windows Install CD now.
7. When booted you should see an option to Format the Hard Drive, select it.
8. After the Drive is formatted you should see a choice to install windows or it start the install itself.
10. When the install is completed remove the Windows Install CD and select to reboot the computer.
11. The Windows Setup will continue the OS Setup after the reboot and then reboot again, you are now in a clean install of Windows.
12. Install the drivers for all your hardware, you may have to reboot several times. (ie; modem, video card, sound card, mouse, printer, scanner, etc.)
13. Install programs.
