Definitly Nv Gefoce 6800 GT. I think it is way better:
1. It has better PS (3.0 - compared to ati 2.1)
2. It is as good in performance as x800xt
3. It is way cheaper (in Poland, so in your country should be the same)
Both this card are high end cards, and also both has great performance, but I think, that 6800gt is better, because it has PS 3.0. Today i have my old geforce 3 ti200, which has PS 1.2. I coul buy geforce 4 mx, which hasn`t it as well instead of GF3Ti. And now friend has GF4 Mx and he can`t play most of games that I can just because of this PS. So think about this.
Ps.
Why don`t you buy GF 6800 Ultra 512mb/256 bit or Radeon X850XT 256/256 ??

Unbelivable machines, but for me 513 mb of 266 mhz ram would be okay

. Why I have so slow computer ...

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