What do you guys think about a 450 or 500 run of the mill power supply for a single 6950? I just bought an ASUS EAH6950 from amazon and didn't think about needing more power for just one card.
For 1 x 6950 it will be fine. I run 2 x 6950's on a 700W.
I have run 1 6950 on a very old, but nice, 450 W PSU and am currently running 2 on a 600 W PSU