My computer has developed a very wierd problem over the past few weeks. It started with my previous power supply going to hell. It lasted for about 4 years, and I've made several upgrades to my computer since. The power supply was 250 volts, and I just figured, about time, right? Wrong. I purchased a new power supply, a substancial increase in power of 580 volts. Like before, my computer will shut down after about 45-60 minutes of being on, and if not shut down, lock up completely. However, the computer turns back on after I hit the button. No problems, no errors, no viruses, no spyware. I've monitored the computer's temperatures, and noted the last shutdown tempature, not even close to over heating. I'm sure it has to do with something hardware, or maybe the way the powersupply's plugs are set up? Not sure what to do next, just a bit of help would be greatly appreciated.

You say that the temperatures are nowhere near overheating, but what were the temperatures?

Many newer motherboards allow you to set a temperature that will cause the system to shut down instantly if the chip gets that hot. Check your BIOS and ensure that this isn't what's occuring.

It gets to about 170+ degrees farenheit. Maybe it is overheating, but I can't find how to set the temperature. How is this the problem though? The old powersupply never had this problem, is this increase in power not good for my computer?

170 degrees Farenheit is approximately 77 degrees Celcius. Your system is running very hot. Ideally, your system should run less than 60 degrees.

You don't set the temperature. The temperature is a readout of what is happening with the system, not a setting that you can modify by playing around in your BIOS settings.

You keep talking about your power supply, but I don't believe that it is the issue. You mentioned that your computer kept restarting before you replaced the power supply and that it still does, which means that the restarting issue is not likely to have anything to do with your power supply. Before you replaced your power supply, did you check the temperatures? I'm sure that the temperature is the main issue with your system shutting off, and I'm sure that the temperature was the issue before you replaced your power supply.

You mention that you have done many upgrades to your system. Have you ever replaced the CPU or the heatsink for it? Think about if your shutting off issue started shortly after you removed and reinstalled the heatsink. If you didn't properly install the heatsink on the processor or have installed a poorly designed heatsink, your chip will overheat.