Desktop

Try to think back to the last time you successfully booted your system. What did you change since then? It sounds like Windows is trying to load some drivers that it does not like, thus its rebooting itself. When you first start to boot the machine, hit F8, boot the machine in "safe mode". If you made any changes like sound card, video, nic card, etc. look in the device manager for those problems. You may also need to run sysedit at the command line to edit the config or autoexec files. Usethe REM command to cancel items in these files.

Good Luck

I've seen this happen when two virus protection programs are trying to scan simultaneously...did you happen to recently add a new virus protection? If so boot to safe mode using F8 on start up (press the key just as you see "Starting Windows" message flash on screen.) Go to start, settings, control panel and click on Add/Remove Programs icon. Choose the program you want to remove and run the uninstall utility. Good Luck

Also bad ram or miss matched ram can cause reboot and a bad power supply or bad fan will overheat cpu and cause reboot.