HV GeForce 6600 WoW 128MB vs NVIDIA GeForce GTX 660

With 5 times as many ROPs and significantly higher graphics frequency, the NVIDIA GeForce GTX 660 graphics card offers considerably better pixel fill rate. Having higher pixel fillrate allows the graphics card to draw more pixels on screen and off screen, which is beneficial for some 3D effects in games, or when playing at higher display resolutions.

There are two factors that affect the maximum texture fillrate, graphics clock rate and the number of TMUs (Texture Mapping Units). The GeForce GTX 660 has a substantial advantage in this area, as it has 10 times as many Texture Mapping Units (TMUs) and operates at much higher frequency. Better texture fill rate means that the graphics card can map more textures and/or use more complex 3D effects for each textured picture element, which improves visual appearance of games and generated images.

To speed up processing, the cards store 3D scene data, textures and intermediate data, used for image generation, in on-board memory. The video memory usually has much higher bandwidth than system RAM, and more bandwidth allows the GPU to run at higher screen resolutions, use larger and more detailed textures, and apply more complex 3D effects and filters. The bandwidth depends on a few components, like memory type, speed, and memory interface width. Specifically, the GeForce GTX 660 graphics card offers better and higher clocked memory, and wider bus interface. As such, it has substantially higher memory bandwidth.