NVIDIA GeForce 6800 GT vs 6800 Ultra Extreme AGP

Because both GPUs have the same number of Raster Operations Pipelines (ROPs) and the NVIDIA GeForce 6800 Ultra Extreme AGP has higher operating frequency, its pixel fillrate is higher. Better pixel fill rate allows more pixels to be drawn on screen per second, which results in increased graphics unit performance, unless there are bottlenecks somewhere else.

In modern games, pixel fillrate is less important than texture fill rate. This parameter is proportional to the number of TMUs (Texture Mapping Units) and graphics clock speed. Since two graphics cards have the same number of Texture Mapping Units (TMUs) and the GeForce 6800 Ultra Extreme AGP graphics card is clocked higher, its texture fillrate is higher. Better texture fill rate means that the GPU can apply more textures and/or use more sophisticated 3D effects for each texel, which improves visual appearance of games and generated images.

To speed up processing, the GPUs 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 graphics card to run at higher display resolutions, use larger and more detailed textures, and apply more complex 3D effects and filters. The bandwidth is dependent on memory type, speed, and memory interface width. Specifically, higher memory bandwidth of the GeForce 6800 Ultra Extreme AGP GPU is due to higher memory clock.