Simply put, Nvidia is better because of the drivers and the function library. TL:DR version ==== Nvidia gives you all the functions and driver responsiveness you need because it does not withhold code/libraries from you in order to sell you a business class card. ATI-AMD has a business class line of openGL cards, these cards exist because most game making/modeling/animation/movie software is based in openGL. To be able to demonstrate superior performance to a corporate buyer, they have to show how much better these "FIREGL" cards are, compared to stock cards. ATI-AMD make this gap in performance artificially larger by skunking how their normal cards handle openGL by removing function libraries. Function libraries are like knowing the answer to a long division problem without having to work it out in pen and paper, knowing them off hand makes you faster, not knowing makes you slower. As a result, with a game or 3D design program, ATI-AMD cards can take almost twice to three times longer for an AMD-ATI card to figure out, almost entirely swallowing up the speed/ performance the higher clock speeds should provide. Nvidia uses a huge built in functions library, and they don't short change their openGL so they can sell pro-class cards, this is why Nvidia is better.