Okay for the last 3 weeks or so my pc has been randomly shutting down as if someone pulled the plug. There are no BSOD, no minidumps, event viewer only showed 1 critical error and that was a kernel power 41, but I have reformatted the hard drive since then and I have yet to get another error. The pc doesn't just shut off during games either, sometimes its idle and sometimes Im on the web. I have ran a memtest and had no errors, I switched the power supply and it happened again, and so I put the previous one back in and right when I put the plug in it started on its own and then quit a few seconds later, both power supplies have done this as I have switched them a few times to make 100% sure it wasn't the psu. I monitor my temps and everything looks fine. Also when it started shutting down it was every 3-4 days, then everyday, then for some reason worked 5 days straight with no problem then started crashing almost daily. Then 2 days ago it was shutting down every 30 minutes and did this 7 times. I have since then switched power supplies and it ran fine for a day so I decided to put the one I had before back in and it is running fine now, although I know its only temporary. So can anyone possibly tell me if it is the motherboard? Would bad caps possibly cause such random shutdowns that can be 30 minutes or days apart? I have also not overclocked anything. Any help on this would be much appreciated. Also if needed my specs are.
Windows Vista 32bit, amd athlon x2 4400+, 450w psu (fsp brand) ati 4850, Motherboard mcp61pm-gm.