What every single person here is telling you is that you don't need anything more than 500ish, at max. If you are going to only accept advice that you are giving to yourself, what is the point of posting threads asking for advice from others? But it is your choice, we are just trying to help is all.
Look: eXtreme Power Supply Calculator
With your specs:
(even with a e8600 which I don't think you have, all you said was "core 2 duo") @ 90% TDP
2xUSB (mouse & kb)
2x120mm fans (no idea what you have)
@ 90% System load, Recommended Minimum PSU Wattage: 240W
550w would be a good one to get if you plan on adding an additional 4850 down the road. I had more than you currently have plus 2x4850 in CF, both overclocked, with a triple core CPU overclocked, and I never came close to maximum draw. So...just sayin