Ihateyou, go for the 6850 dicrectCU TOP from asus, i have it and it's amazing. All the reviews say it's MUCH better then then the standard 6870 and it's cheaper plus it has extra headroom for even more OCing then what it comes with out of the box. I have it at standard settings to preserve life and so far the only time's it's failed to run games at a decent FPS is on games with shitty engines like oblivion which is based on the gambryo engine. It can run RAGE, Crysis 2 and many other games on max settings at 1680X1050 at decent fps (read 30+ fps), RAGE plays at 50-60 FPS contantly for example.
p.s. gambryo is a true shitfest, our university computers had the engine in raw form and it was SOOO buggy, I talked with other's who were using it and they told me how it was unstable, prone to random crashing (worked one moment and not the next for the exact same segment) and they often had to re-write parts of the engines code to get it work properly.
EDIT: check out this graphics card teir thing from toms hardware, it puts the 6850 near the top
http://www.tomshardware.com/reviews/best-graphics-card-gaming-performance,3042-7.html
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