The new Enermax's are supposed to be sweet and stable. It isn't single railed though. the 1250w is like $339 and has six 12v rails @ 30A
Something else to keep in mind is true power draw. If you are gonna game with the rig at high res, the vid cards will consume much more power. If it's just for benching you'll use less. Some bencher from Europe had a Kilo-Watt meter on his ln2 cooled i7, 2x4870x2, and other goodies. He said he saw 980-ish watts being pulled from the wall during vantage. Now multiply that by the efficiency of the PSU you have and bingo!! There is your power usage of that rig.
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