Compare any two graphics cards:
GeForce GTX 580 vs Radeon HD 7870
IntroThe GeForce GTX 580 makes use of a 40 nm design. nVidia has clocked the core speed at 772 MHz. The GDDR5 RAM runs at a frequency of 1002 MHz on this specific card. It features 512 SPUs along with 64 Texture Address Units and 48 Rasterization Operator Units.
Compare that to the Radeon HD 7870, which uses a 28 nm design. AMD has clocked the core frequency at 1000 MHz. The GDDR5 memory is set to run at a speed of 1200 MHz on this specific model. It features 1280 SPUs along with 80 TAUs and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The GeForce GTX 580, in theory, should be a lot faster than the Radeon HD 7870 overall. (explain)
Texel RateThe Radeon HD 7870 is a lot (more or less 62%) better at texture filtering than the GeForce GTX 580. (explain)
Pixel RateThe GeForce GTX 580 is just a bit (approximately 16%) better at FSAA than the Radeon HD 7870, and should be able to handle higher 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 max amount of data (in units of megabytes per second) that can be transported across the external memory interface in a second. It is calculated by multiplying the card's interface width by the speed of its memory. In the case of DDR type RAM, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the bandwidth is, the faster the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed in one second. This figure is worked out by multiplying the total number of texture units of the card by the core speed of the chip. The better this number, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip can possibly write to the local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate also depends on quite a few other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.