When I play games or run stress tests on my custom built, my system will shut down. It's not a heat issue, temps are all fine. It's not a driver or virus issue, I've taken every measure I can think of to address that. It's not bad RAM as I have tested it with positive results. The only thing I can think of is my 3 month old 650w psu. Does this sound like the problem? I mean, the only time the PC will ever just shut down is under a heavy load, not just randomly. What do you guys think? Is this failing psu behavior?