Compare any two graphics cards:
GeForce GTX 580 vs Radeon HD 7970
IntroThe GeForce GTX 580 has a core clock frequency of 772 MHz and a GDDR5 memory speed of 1002 MHz. It also makes use of a 384-bit memory bus, and makes use of a 40 nm design. It features 512 SPUs, 64 Texture Address Units, and 48 ROPs.
Compare those specs to the Radeon HD 7970, which features a clock speed of 925 MHz and a GDDR5 memory frequency of 1375 MHz. It also uses a 384-bit memory bus, and uses a 28 nm design. It is comprised of 2048 SPUs, 128 Texture Address Units, and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Performance-wise, the Radeon HD 7970 should in theory be quite a bit superior to the GeForce GTX 580 overall. (explain)
Texel RateThe Radeon HD 7970 will be a lot (approximately 140%) faster with regards to texture filtering than the GeForce GTX 580. (explain)
Pixel RateThe GeForce GTX 580 is a lot (about 25%) better at full screen anti-aliasing than the Radeon HD 7970, and will be capable of handling higher screen 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.
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 maximum amount of data (counted in megabytes per second) that can be transferred past the external memory interface in one second. It is worked out by multiplying the interface width by its memory speed. If the card has DDR RAM, it 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 high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are applied in one second. This 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 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 maximum number of pixels the video card can 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 - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate is also dependant on lots of 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.