Compare any two graphics cards:
GeForce GTX 580 3GB vs Radeon HD 5970
IntroThe GeForce GTX 580 3GB has a GPU core clock speed of 772 MHz, and the 3072 MB of GDDR5 memory is set to run at 1002 MHz through a 384-bit bus. It also features 512 Stream Processors, 64 TAUs, and 48 Raster Operation Units.
Compare those specs to the Radeon HD 5970, which features clock speeds of 725 MHz on the GPU, and 1000 MHz on the 1024 MB of GDDR5 RAM. It features 1600 SPUs as well as 160 Texture Address Units and 64 Rasterization Operator Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 5970 should in theory be much faster than the GeForce GTX 580 3GB in general. (explain)
Texel RateThe Radeon HD 5970 will be a lot (more or less 370%) faster with regards to anisotropic filtering than the GeForce GTX 580 3GB. (explain)
Pixel RateThe Radeon HD 5970 is quite a bit (more or less 150%) better at full screen anti-aliasing than the GeForce GTX 580 3GB, and should be capable of handling higher resolutions better. (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: Memory bandwidth is the largest amount of information (in units of megabytes per second) that can be transferred past the external memory interface within a second. The number is calculated by multiplying the card's bus width by its memory clock speed. If it uses DDR RAM, it should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are applied per second. This is worked out by multiplying the total number of texture units of the card 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 processed per second.
Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card could possibly record to its local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of Render Output Units by the the core speed of the card. 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 quite a few other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.