In several benchmarking tests, the NVidia 6800 Ultra outperformed the Radeon x800 by 20% across the board as well as 15% in visual quality including Open GL and DirectX.. the GeForce 6800 Ultra is the ultimate card at the moment, the Radeon X800 is next, then the Geforce 6800 standard, then Radeon X500, then Geforce 6800 GT then Radeon x300... that is how the benchmarking shows performance of the cards and visual quality during high end testing.. for the end user gamer, any games from 2003 and back should have no visual difference when used on either Radeon X*** or 6800 card.. the performance comes out in DirectX 9.0c coded games from 2003 up and even then there is little to no difference to the naked eye unless you are doing high end video work for like a movie company in CGI (LOTR comes to mind here).. at this point if you are doing this type of detailed work, the Geforce 6800 Ultra is the best way to go.