My PC won't stay powered on.

[medeli]

About a week ago, I was on my PC and it kept shutting off. When it reboots, there isn't an error message or anything. It boots fine and then turns off anywhere from 1-15 minutes later. Anyone know what the problem may be? I know squat about computers

 

[chookman]

Sounds like PSU or overheating... need some specs to know anymore