Compare any two graphics cards:
GeForce GTX 660 vs Radeon HD 7850
IntroThe GeForce GTX 660 has a GPU core speed of 980 MHz, and the 2048 MB of GDDR5 memory runs at 1502 MHz through a 192-bit bus. It also features 960 SPUs, 80 Texture Address Units, and 24 Raster Operation Units.
Compare those specifications to the Radeon HD 7850, which comes with core speeds of 860 MHz on the GPU, and 1200 MHz on the 2048 MB of GDDR5 RAM. It features 1024 SPUs along with 64 Texture Address Units and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 7850 should in theory perform just a bit faster than the GeForce GTX 660 in general. (explain)
Texel RateThe GeForce GTX 660 should be quite a bit (approximately 42%) faster with regards to texture filtering than the Radeon HD 7850. (explain)
Pixel RateIf using lots of anti-aliasing is important to you, then the Radeon HD 7850 is superior to the GeForce GTX 660, not by a very large margin though. (explain)
Please note that the above 'benchmarks' are all just theoretical - the results were calculated based on the card's specifications, and real-world performance may (and probably will) vary at least a bit.
Please note that the price comparisons are based on search keywords - sometimes it might show cards with very similar names that are not exactly the same as the one chosen in the comparison. We do try to filter out the wrong results as best we can, though.
Memory Bandwidth: Bandwidth is the max amount of information (in units of megabytes per second) that can be transported past the external memory interface in one second. It is worked out by multiplying the card's interface width by its memory clock speed. If the card has DDR RAM, it must be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed per second. This is calculated by multiplying the total number of texture units of the card by the core speed of the chip. The higher the texel rate, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.
Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card can possibly write to the local memory in one second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate also depends on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the maximum fill rate.