The GTX would be overkill for your system if you wan the best performance. If you are going to wait for the 8900, wait for R600. If the R600 cards don't outperform the G80, you should see price drops and thus you win. If R600 cards perform better, buy one of them and again, you win. If your don't need the best of the best RIGHT NOW, then wait. If you need a card I would recommend the GTS based on your res and CPU. The GTS may not be the best but it still out performs ATi current cards and is cheaper than the GTX.
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