The 1st thing I would suspect is that the power supply is bad or not powerful enough to drive all your computer's inards. Try switching it out , if you can.
2nd make sure that the bottom of the motherboard isn't touching any part of the computer's case. If it is then the computer is shorting out. You could then try placing a piece of cardboard between the MB and the case to insulate it.
3rd disable any "power management" setting in both the operating system and the BIOS.
The last thing to check for is bad memory. The only way to test is to switch out memory sticks to see if that makes a difference.
Hopfully others will have some more ideas.
[This message has been edited by Ghost_Hacker (edited 02-21-2002).]
Ferengi Rules of Acquistion:
Rule # 47 Don't trust a man wearing a better suit than your own.