What make and model of power supply are you using? For that matter, what are the specs of your overall system?
I'm not sure on the power supply yet but I'm thinking around 500 watt Power Supply. I have the i5-760 LGA1156 Processor, Corsair XMS3 4Gb DDR3, Asus P7P55D-E LX Motherboard, Western Digital 1TB HDD. I hope this helps.