Compare any two graphics cards:
GeForce GTX 580 vs Radeon HD 7970
IntroThe GeForce GTX 580 makes use of a 40 nm design. nVidia has clocked the core frequency at 772 MHz. The GDDR5 memory is set to run at a frequency of 1002 MHz on this particular model. It features 512 SPUs along with 64 Texture Address Units and 48 ROPs.
Compare those specs to the Radeon HD 7970, which has core clock speeds of 925 MHz on the GPU, and 1375 MHz on the 3072 MB of GDDR5 RAM. It features 2048 SPUs as well as 128 TAUs and 32 Rasterization Operator Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically, the Radeon HD 7970 should perform a lot faster than the GeForce GTX 580 in general. (explain)
Texel RateThe Radeon HD 7970 should be a lot (approximately 140%) faster with regards to texture filtering than the GeForce GTX 580. (explain)
Pixel RateThe GeForce GTX 580 will be quite a bit (more or less 25%) faster with regards to FSAA than the Radeon HD 7970, and also able to handle higher screen resolutions without losing too much performance. (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 (counted in MB per second) that can be transferred across the external memory interface in a second. It is calculated by multiplying the bus width by the speed of its memory. If the card has DDR type memory, the result should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the bandwidth is, the better the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed in one second. This figure is calculated by multiplying the total number of texture units by the core speed of the chip. The better the texel rate, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.
Pixel Rate: Pixel rate is the most pixels the video card could possibly write to the local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the number of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate is also dependant on quite a few other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.