Where do people get this nonsense? It's 2013 you don't need a 1000w PSU anymore.
Total system power consumption 336w, that also takes into account power wasted by the PSU, and thats with an overclocked 3960X. I had a 670 (which uses more power than a 760) running on a 500w PSU for about 8 months, and not once did the PSU catch fire or explode. OP, 500w is well more than whats needed.