Compare any two graphics cards:
GeForce GTX 580 3GB vs Radeon HD 5970
IntroThe GeForce GTX 580 3GB comes with a clock frequency of 772 MHz and a GDDR5 memory speed of 1002 MHz. It also uses a 384-bit bus, and makes use of a 40 nm design. It features 512 SPUs, 64 TAUs, and 48 Raster Operation Units.
Compare all of that to the Radeon HD 5970, which features a core clock frequency of 725 MHz and a GDDR5 memory speed of 1000 MHz. It also uses a 256-bit bus, and uses a 40 nm design. It is comprised of 1600 SPUs, 160 Texture Address Units, and 64 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically, the Radeon HD 5970 should be a lot faster than the GeForce GTX 580 3GB in general. (explain)
Texel RateThe Radeon HD 5970 should be quite a bit (approximately 370%) better at texture filtering than the GeForce GTX 580 3GB. (explain)
Pixel RateIf using a high screen resolution is important to you, then the Radeon HD 5970 is the winner, by far. (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.
One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.
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 largest amount of data (counted in megabytes per second) that can be transferred across the external memory interface in one second. It's calculated by multiplying the card's interface width by the speed of its memory. If it uses DDR type RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are processed in one second. This number is calculated by multiplying the total number of texture units of the card by the core clock 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 processed in a second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card could possibly write to the local memory in one second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of Render Output Units by the the core speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate is also dependant on lots of other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the max fill rate.