Answer
This question was answered on December 8, 2003.
Much of the information contained herein may have changed since posting.
There is a device either a internal device or external device (USB device) that is consuming alot of power and is keeps damaging your computer power supply. either by a power supply that has more wattz or reduce the amount of device that is attach to your computer.
It could be your hard drive, the device the consume more power is the hard drive. So if you have four hard drive or SCSI hard drive then by a new power supply that can increase more volts for your system and devices.
Don't put to many devices in the USB Hub is you have one. Reduce as it can. Check also to see if your Power Fan is moving and working properly. The same thing with the CPU FAN, its very important to have a cool temperature inside you computer. So if your computer is acting strange then this mean that your computer is producing alot of heat and can damage some components. Be sure to see if all fan is working as well the room where the computer is in is cool enough.