Someone told me 550 wat isnt enough for this set up! Im pretty sure it will surfice. Although I am having problems getting my PC to post sometimes (50% of the time). Could this be true? The MB does suck a 24 pin + 8 pin + 4 Pin Molex Ez Plug. This seems like a lot but im pretty sure 550 wat is plenty.
I saw 530 wt and 580 wt models, but no 550's. Either way, with what you have it should be fine. As for the post problems, look for a loose connection in wiring, sockets, ram, and cards. Something that might be getting juice sometimes, but not always.