Compare any two graphics cards:
GeForce GTX 590 vs Radeon HD 6990
IntroThe GeForce GTX 590 comes with clock speeds of 607 MHz on the GPU, and 855 MHz on the 1536 MB of GDDR5 RAM. It features 512 SPUs along with 64 TAUs and 48 Rasterization Operator Units.
Compare that to the Radeon HD 6990, which uses a 40 nm design. AMD has set the core speed at 830 MHz. The GDDR5 RAM runs at a speed of 1250 MHz on this specific card. It features 1536 SPUs as well as 96 Texture Address Units and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The GeForce GTX 590 should in theory be a little bit faster than the Radeon HD 6990 in general. (explain)
Texel RateThe Radeon HD 6990 will be quite a bit (more or less 105%) more effective at anisotropic filtering than the GeForce GTX 590. (explain)
Pixel RateThe GeForce GTX 590 will be a small bit (about 10%) more effective at anti-aliasing than the Radeon HD 6990, and also capable of handling higher resolutions while still performing well. (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 max amount of data (counted in MB per second) that can be transferred across the external memory interface in one second. It is calculated by multiplying the interface width by the speed of its memory. If the card has DDR memory, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are applied in one second. This figure is worked out by multiplying the total 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 handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics card could possibly record to the local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of Render Output Units by the clock speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate is also dependant on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the max fill rate.