You can get something better than that, is $170 your budget?
And are you just upgrading the graphics card or are you building a new system?
If you can fork out another $50 or adjust your setup so you can get the X800GTO2 for $220, as far as I've heard, they are still moddable to the X850XTPE. Otherwise you can get a X800GTO for $169 which should be better than your X800GT as long as you don't play at lower resolution, because then you really wouldn't see a difference.
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