[stalker789]

I am working on a Gateway 3250S with Windows XP, it would sometimes boot up, but shut down after about 5 mins. Then after that it repeatedly starts and shuts down before the video kicks in. I checked the memory with known working memory, still the same result. I tested the power supply and it was good, but still replaced it with a know good power supply to be sure, same thing. I also put in a known working Video card.
I disconnected all drives and just booted the board to see if it was a problem with a drive, same result. I added thermal paste to the CPU just incase it was overheating, still nothing. So, I purchased a new motherboard, the same board and at first it ran great, I ran it for 5 hours with no problems. The next day I went to turn it on and back to the same problem. I am leaning toward the CPU as the problem, I did not replace it with the new board. If anyone has any other thoughts I would greatly appreciate it. Thank you !!

[Dave Hybrid]

Have you tried doing a fresh install of XP, it could be corrupt.

[gkr]

Some malicious programs might have attacked your hard drive. Check the system- hidden files in all of your hard drives. Some times they are autorun.exe files. Then it is really tough to help you. But you can delete those files and run it properly.