Compare any two graphics cards:
GeForce GTX 580 3GB vs Radeon HD 5970
IntroThe GeForce GTX 580 3GB features a GPU core speed of 772 MHz, and the 3072 MB of GDDR5 memory is set to run at 1002 MHz through a 384-bit bus. It also is made up of 512 Stream Processors, 64 TAUs, and 48 ROPs.
Compare those specs to the Radeon HD 5970, which features GPU clock speed of 725 MHz, and 1024 MB of GDDR5 memory set to run at 1000 MHz through a 256-bit bus. It also features 1600 SPUs, 160 Texture Address Units, and 64 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically, the Radeon HD 5970 should be much faster than the GeForce GTX 580 3GB in general. (explain)
Texel RateThe Radeon HD 5970 will be quite a bit (approximately 370%) more effective at AF than the GeForce GTX 580 3GB. (explain)
Pixel RateIf running with lots of anti-aliasing is important to you, then the Radeon HD 5970 is a better choice, and very much so. (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 data (in units of MB per second) that can be transported past 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 RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied in one second. This figure is calculated by multiplying the total number of texture units by the core speed of the chip. The higher the texel rate, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.
Pixel Rate: Pixel rate is the most pixels the video card could possibly record to its local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the amount of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate also depends on quite a few other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the max fill rate.