Compare any two graphics cards:
GeForce GTX 590 vs Radeon HD 6990
IntroThe GeForce GTX 590 comes with 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 Texture Address Units and 48 ROPs.
Compare those specs to the Radeon HD 6990, which features GPU clock speed of 830 MHz, and 2048 MB of GDDR5 memory running at 1250 MHz through a 256-bit bus. It also is comprised of 1536 Stream Processors, 96 TAUs, and 32 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The GeForce GTX 590, in theory, should be a small bit faster than the Radeon HD 6990 overall. (explain)
Texel RateThe Radeon HD 6990 should be a lot (about 105%) more effective at AF than the GeForce GTX 590. (explain)
Pixel RateThe GeForce GTX 590 should be a little bit (approximately 10%) more effective at anti-aliasing than the Radeon HD 6990, and should be capable of handling higher 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.
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 max amount of information (measured in MB per second) that can be moved across the external memory interface in one second. The number is calculated by multiplying the interface width by its memory clock speed. In the case of DDR RAM, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed in one second. This number is calculated 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 texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip could possibly write to the local memory in a 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 - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate is also dependant on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the max fill rate.