Compare any two graphics cards:
GeForce GTX 660 vs Radeon HD 7850
IntroThe GeForce GTX 660 features a clock speed of 980 MHz and a GDDR5 memory frequency of 1502 MHz. It also makes use of a 192-bit bus, and makes use of a 28 nm design. It is made up of 960 SPUs, 80 Texture Address Units, and 24 Raster Operation Units.
Compare all that to the Radeon HD 7850, which comes with clock speeds of 860 MHz on the GPU, and 1200 MHz on the 2048 MB of GDDR5 memory. It features 1024 SPUs as well as 64 Texture Address Units and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 7850 should perform a little bit faster than the GeForce GTX 660 in general. (explain)
Texel RateThe GeForce GTX 660 should be a lot (approximately 42%) better at AF than the Radeon HD 7850. (explain)
Pixel RateIf using a high screen resolution is important to you, then the Radeon HD 7850 is a better choice, 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 maximum amount of information (counted in megabytes per second) that can be moved past the external memory interface in a second. It's worked out by multiplying the card's interface width by its memory clock speed. In the case of DDR memory, it must be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the faster the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed in one second. This is calculated by multiplying the total number of texture units of the card by the core clock speed of the chip. The better this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.
Pixel Rate: Pixel rate is the most pixels that the graphics chip could possibly write to the local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the amount of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate is also dependant on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the maximum fill rate.