Stops working for no reason

[skalderis]

Thanks for replies. Got Corsair AX850, which gets good reviews. I measured whole PC's power consumption on load - 280W. And I run default clocks for my HD5850.

My CPU is overclocked. Q6600 2.4 to 3.2ghz for 4 years now. Could that be a problem? Tested with LinX, no faults.