
Well, it really depends on what game you will be playing. But the card that myself and all my gamer buds use is the GeForce 6800. If you really want to go high quality, you can get the ultra, but my games, including unreal tournament 2004, works fine on the plain old 6800. You could get the gt, but I don't really know what that offers. But there is a stark difference between the regular 6800 and the ultra. My boss plays the newest counter strike with the new steam engine and his ultra plays perfect of full video settings.
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Top 5 Power Graphics Cards
These are the top power graphics cards today, but ratings and rankings can change quickly due to pricing and technology changes, so check back frequently for the latest info.
Ref. https://www.pcworld.com/reviews/article/0,a...k,wbxrvw,00.asp