Hi everyone, my PC keeps on shuttng down everytime after 1 minute to 3 minute after starting up. Sometimes the window start up ok then shut down itself. Even if I go to the BIOS setup, it does not give me enough time to reset to default settings. I unplug everything out except the hard drive, still the same problem. Fully tested the PSU and it's all ok. Take the hard drive out and put it on another computer, the computer have no problem. Put a working hard drive on the PC I am having problem with, still the same thing, not it's only start up for only half a minute, no mater whether I am on he BIOS setting or the window safe mode, still shut down after a few minutes. Please any suggestion for what to do next, I have a funny feelings that my CPU is toasted but I dont know how to prove that.

If the CPU is over heating is will shut down like that, check to see if the fan on the CPU's heat sink is working properly and that the heat sink is properly connected. Also look for accumulated dust.

Yup. Since its doing this even in the BIOS, this has got to be a heating issue. Also, run a few diagnostics on y our memory, or try installing known working memory cards in the system