Compare any two graphics cards:
GeForce GTX 590 vs Radeon HD 6990
IntroThe GeForce GTX 590 uses a 40 nm design. nVidia has clocked the core speed at 607 MHz. The GDDR5 memory runs at a frequency of 855 MHz on this particular model. It features 512 SPUs along with 64 Texture Address Units and 48 ROPs.
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 is set to run at a speed of 1250 MHz on this particular model. It features 1536 SPUs as well as 96 TAUs and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The GeForce GTX 590 should in theory perform a bit faster than the Radeon HD 6990 in general. (explain)
Texel RateThe Radeon HD 6990 will be a lot (about 105%) more effective at texture filtering than the GeForce GTX 590. (explain)
Pixel RateThe GeForce GTX 590 will be a small bit (about 10%) better at FSAA than the Radeon HD 6990, and also able to handle higher screen resolutions more effectively. (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 information (measured in megabytes per second) that can be transferred across the external memory interface within a second. It's calculated by multiplying the card's interface width by its memory clock speed. If it uses DDR type memory, the result should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the 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 texture map elements (texels) that can be applied in one second. This figure is calculated by multiplying the total texture units of the card by the core speed of the chip. The higher this number, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.
Pixel Rate: Pixel rate is the most pixels the graphics card could possibly record to the local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate is also dependant on quite a few other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the max fill rate.