Need full specs of hardware including the make and model number of everything including: motherboard, hard drive, CD drive, power supply, all attached equipment, etc. etc. etc.... you can never give too much information. Something small and seemingly unimportant could be the source of a problem, so knock yourself out and just give every bit of info you can.
Sounds like a short, but before jumping to conclusions and making any suggestions to fix it, best to know what you're working with here.
