I have been lurking a lot but I had to chirp in with my humble findings to try to help out.
First off, the case. That is one big case. I don't think you can quite grasp how big it is unless you have seen it before. I would suggest a roomier mid-tower if you will just have a run of the mill gaming pc.
Second, the HDD. Never buy Caviar Blues as your main HDD. They are far less reliable than Blacks, you are better off shelling out the $20-30 for better HDD. Stay away from Greens, I don't know if it has been changed but they had a problem with the needles which caused extraoridnary failure rates.
Third, the mobo. Not to hate on Gigabyte but there is a reason why their mobos are so cheap. Often their expansion slots share badnwidth moreso than other mobos and some other random stuff like that (example: you couldint use USB3 and 2 GPUs without one of the slots goign into x8 mode, on one of their mobos, maybe i wasnt this exact combination of components bu it was something like that). Also they seem to have worse failure rates than others, and as a second-hand story-teller tht seems to be true.
CPU or GPU: These don't match. The 480 will absolutely eat away at your CPU and your CPU will basically bottleneck your games because it can't keep up, even when overclocked. I know the 965 is the most bang for your buck, but if you are going with a 480 get something that doesn't spit in its face. At the very least get a i7-930 and overclock that at the least. Or if you like the 965 so much get a gtx 460 instead of a 480. I'd suggest at the least an i7-930 overclocked to wrangle the beast that is the 480. Of course then you should get some triple-channel RAM.
The PSU: Too much, unless you are going to SLI 480's don't bother with so much, even a 750-800 will leave you with plenty of power of a single 480, even when overclocked.
Lastly, more of an addition than a critique on what you have, get liquid cooling. If you stick with the 480 get it liquid cooled. That card wa meant to be cooled with some hardcore stuff. From what I have seen the biggest bottleneck for this beast is the temperature. The 480 scales like a monster when overclocked and it is just mindblowing the results you get when you liquid cool it. Also all the GTX 400's scale ridiculously well in SLI, somethign to think about down the road.
