+ 0 Votes Reputable power supply. mike.laing April 4, 2013 at 4:18am PST Is your PSU a Coolermaster or Thermaltake X2 or some such? No-name type PSU put out a lot less than they are rated. Now, I just sold a system with a 500W Thermaltake TR2. The system was an i7 920 on a Gigabyte X58 UD5 board, and a GTX 650 Ti. The processor was overclocked to 3.8 GHz, and I ran Prime95 on all 8 processor threads for several hours with no errors. Running Furmark graphics benchmark, my graphics card went to 89 degrees C and my processor to 74, so make sure you have good cooling. I was running a 200 and three 120mm fans plus the Coolermaster Evo 212. All this on a 500W PSU. If you are going to go hard, then, just to be safe, get at least a 600W, but I suspect 500 might be good enough for most gaming.