I bought a new gtx670 6 days ago, and I've been using it rarely. But today , my display turned black and the pc restarted when I was playing skyrim. And the pc was restarting every time it tries to boot. I installed a new copy of windows but it also didn't boot and kept restarting. It only booted when I plugged my old 9400gt. So please tell me what to do
That's a good start, but are you sure it can provide sufficient amperes on the respective power rails? Not all PSUs are created equal, and some PSU makers will flat out lie about the level of power they can deliver.