Re: Which one?
For starters there is a decent price and performance gap between those two cards. The 5850 is more comparable to a GTX 285, even then it significantly outperforms it. So if you can get your hands on the the 5850 and have the extra money for it, it's both more powerful and more future-proof (DX11).
So no question really, unless price is a huge concern. 5850.
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