Compare any two graphics cards:
GeForce GTX 590 vs Radeon HD 6990
IntroThe GeForce GTX 590 has core speeds of 607 MHz on the GPU, and 855 MHz on the 1536 MB of GDDR5 memory. It features 512 SPUs as well as 64 TAUs and 48 Rasterization Operator Units.
Compare that to the Radeon HD 6990, which comes with GPU core speed of 830 MHz, and 2048 MB of GDDR5 RAM running at 1250 MHz through a 256-bit bus. It also is made up of 1536 Stream Processors, 96 Texture Address Units, and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically, the GeForce GTX 590 should perform a small bit faster than the Radeon HD 6990 overall. (explain)
Texel RateThe Radeon HD 6990 will be a lot (more or less 105%) more effective at AF than the GeForce GTX 590. (explain)
Pixel RateThe GeForce GTX 590 will be a bit (more or less 10%) better at anti-aliasing than the Radeon HD 6990, and also will be able to handle 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 (counted in MB per second) that can be moved over the external memory interface in one second. The number is calculated by multiplying the card's bus width by the speed of its memory. If it uses DDR memory, the result should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, the faster the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are applied per second. This is worked out by multiplying the total texture units of the card by the core clock speed of the chip. The higher this number, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.
Pixel Rate: Pixel rate is the most pixels that the graphics card could possibly record to the local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the number of colour ROPs by the the card's 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 output rate also depends on lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.