Yep, don't ignore the PSU quality. It's perhaps the most important component, yet often the most ignored since it has less of a "bling" aspect to it.
As larva stated, a AX500-A Fortron would be a minimum choice, and with the second revision, definitely good enough. I don't really like the X700 series as well, and bumping that to either an x800 series, 6600GT or a 6800nu would be better.