8800ULTRA = 8800GTX OC'd look @ mine

Also i agree about the 8800GTS 512 it has the performance of GTX for less price u can say that GTX isnt worth it :
http://www.hothardware.com/articles/NVIDIA_GeForce_8800_GTS_Refresh_Asus_and_XFX/?page=11
enerally speaking though, the GeForce 8800 GTS 512MB’s performance is better than the original 640MB GTS and the relatively new 8800 GT and on-par with the GeForce 8800 GTX at lower resolutions. Crank up the resolutions, however, and the GTX (or Ultra) is still the king of the hill.