well for ati its: SE, Pro, XT with SE being the worst... and for nvidia its different....like for the 6 series its: regular, GT, & Ultra..... i for got the order for the GeForce FX series tho....
i was lookin at a ati Raedon 9600le, the difference in price compared to the 9600XT is more than double i don't know if it would b justified in my situation.