If you want the top of the market card get the GTX 295. I currently own it, and at the time it was $500 bucks.
http://www.nvidia.com/object/product_ge ... 95_us.html
It is still currently around $500 Bucks.
The card is well made, and the graphics are just f***ing insane. Love playing ET at highest quality, mirrors edge, left 4 dead, team fortress 2, Crysis, etc.
It's a total beast.