ASUS Radeon R7 265 DirectCU II vs NVIDIA GeForce GTX 660

Despite of slower graphics clock, the ASUS Radeon R7 265 DirectCU II graphics card comes with higher pixel fill rate, thanks to many more ROPs. Better maximum pixel fill rate allows more pixels to be drawn on screen per second, and is an indication of better GPU performance, unless there are bottlenecks in other areas, such as texture fillrate, CPU speed or memory bandwidth.

The NVIDIA GeForce GTX 660 has more TMUs (Texture Mapping Units) than the ASUS Radeon R7 265 DirectCU II graphics unit. What's more, its graphics frequency is higher, as a consequence, its texture fillrate is higher. Better texture fill rate means that the card can use more sophisticated 3D effects and/or map more textures to each texel, which improves visual appearance of games and generated images.

Single Precision performance is convenient for estimating card's maximum speed in applications, that process primarily single-precision floating point data. This performance is measured in GFLOPS or billions of Floating Point Operations Per Second. As a rule, the faster stream processors or CUDA cores run at, and the more cores / processors the graphics card has, the higher Single Precision performance will be. The GeForce GTX 660 is slightly faster here. Higher single-precision performance number means the graphics card will perform better in general computing applications. Since CUDA cores or stream processors are also used as vertex and geometry shaders for 3D image generation, higher performance is also beneficial to games.

To speed up processing, the graphics 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 graphics card to run at higher display resolutions, use larger and more detailed textures, and apply more complex 3D effects and filters. The bandwidth depends on memory type, speed, and width of memory interface. Specifically, higher memory bandwidth of the ASUS Radeon R7 265 DirectCU II GPU is a result of wider memory bus.