What voltage PSU is adequate, using a GTX 560 GPU?

Falcon66

Honorable
Jul 16, 2012
23
0
10,510
Hey guys. I'm doing a budget first build, using a GTX 560 GPU:

CPU: Intel Core i5-2500K 3.3GHz Quad-Core Processor
Motherboard: ASRock Z77 Extreme4 ATX LGA1155 Motherboard
Memory: G.Skill Ripjaws X Series 8GB (2 x 4GB) DDR3-1600 Memory
Hard Drive: Seagate Barracuda 1TB 3.5" 7200RPM Internal Hard Drive
Video Card: EVGA GeForce GTX 560 1GB Video Card (NVIDIA recommends minimum 450W PSU)
Case: Cooler Master HAF 912 ATX Mid Tower Case
Optical Drive: Asus BC-12B1ST/BLK/B/AS Blu-Ray Reader, DVD/CD Writer
Optical Drive: Sony AD-7280S-0B DVD/CD Writer
Operating System: Microsoft Windows 7 Home Premium SP1 (64-bit)

I'm trying to nail down the right voltage PSU given my graphics card, but my research is leading me in circles despite the great content here at Tom's. I can't find consistent power consumption specs across different websites. Various online calculators give drastically different estimates (though http://extreme.outervision.com/psucalculatorlite.jsp seems pretty good). Personal opinions across different forums vary widely. Before I start convulsing and bleeding from the eyes, I would appreciate a bit of help here.

Can anybody offer me their learned opinion of what voltage is appropriate for my PSU? I'd like to preserve the option to overclock at some future date; am not sure how much extra wattage that would require.

Much obliged! Thanks...