PC isn't working correctly anymore, what component is the problem here?

Dragonhunter990

Honorable
Jul 12, 2013
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10,630
Some time ago my PC wouldn't boot anymore. Well, actually, it would, but it would reboot 2 minutes after. And again. And again. I sent my PC back to the company where I bought it and they put in a new mobo and new RAM sticks. At first I thought my PC was working again, but then I got a BSOD. And then my PC kept crashing. They sent me a new HDD because it could be a software problem. I put in the new HDD and installed Windows.

I still get Blue Screens, so it must be a hardware problem. What could it be? PSU? CPU?