Not everything is about all out performance. The 7 series is hands down the champ for performance per watt.
Thanks for the suggestion and for my case I think the 6870 is a better choice just because of the price and wattage, and at this point anything is better than looking at windows 7(in general) or YouTube with an 8 bit gpu.
the HD 7850 is better than the 6950. it consumes power like a low end card but performs beastly. it can also be overclocked easily to perform like a GTX 570 or better.
Kind of a dead horse... I'm not arguing against you, but within the constraints set forth by fishbelt, the 6950 gives the best performance. The 7850 is above his price limit, he mentioned BF3 and the 6950 outperforms the 7850 in that bench. It also fits within his 500w PSU limit. Had he asked for a card in the $230 range, I may well have suggested the 7850.