You have mostly upper end parts, but a mediocre PSU. In short, don't
skimp on the PSU.
Do you plan on buying a second video card? I ask because 500w is more than enough for any single-GPU system.
If you want 2 video cards, this is about the cheapest PSU I would put in the systemPower Supply: XFX 750W 80 PLUS Bronze Certified ATX12V / EPS12V Power Supply
($84.99 @ NCIX US)
If you want to stick with one video card, this onePower Supply: XFX 550W 80 PLUS Bronze Certified ATX12V / EPS12V Power Supply
($53.99 @ NCIX US)
Other than that, looks good.