Compare any two graphics cards:
GeForce GTX 580 3GB vs Radeon HD 5970
IntroThe GeForce GTX 580 3GB makes use of a 40 nm design. nVidia has clocked the core frequency at 772 MHz. The GDDR5 RAM is set to run at a frequency of 1002 MHz on this specific model. It features 512 SPUs as well as 64 Texture Address Units and 48 Rasterization Operator Units.
Compare those specifications to the Radeon HD 5970, which comes with a core clock frequency of 725 MHz and a GDDR5 memory speed of 1000 MHz. It also features a 256-bit bus, and makes use of a 40 nm design. It is made up of 1600 SPUs, 160 TAUs, and 64 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 5970 will be 33% quicker than the GeForce GTX 580 3GB in general, due to its higher bandwidth. (explain)
Texel RateThe Radeon HD 5970 should be a lot (approximately 370%) more effective at AF than the GeForce GTX 580 3GB. (explain)
Pixel RateThe Radeon HD 5970 will be a lot (more or less 150%) faster with regards to anti-aliasing than the GeForce GTX 580 3GB, 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 largest amount of information (in units of megabytes per second) that can be moved across the external memory interface in one second. It's worked out by multiplying the interface width by the speed of its memory. If it uses DDR RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better 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 are applied per second. This figure is calculated by multiplying the total texture units of the card by the core speed of the chip. The better this number, the better the graphics 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 amount of pixels that the graphics card could possibly write to the local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.