Did you mean a X800 Pro or a 6800? or are you really deciding between the much slower 9800 Pro and the much faster 6800? well if this is the case then I would go with the 6800 but if you are deciding between the x800 Pro and the 6800 GT then I would flip a coin because both have there advantages, and if you would be deciding between a X800 XT and a 6800 Ultra I would again flip a coin, but keep in mind that the 6800 ULTRA is about 100 to 150 US cheaper, now if you have a tight cash flow I would go with the ASUS 6800 v9999 because it is one of the next generation cards and it is fast and overclockable and it is a good buy for the buck.