Compare any two graphics cards:
GeForce GTX 580 vs Radeon HD 7970
IntroThe GeForce GTX 580 features a GPU clock speed of 772 MHz, and the 1536 MB of GDDR5 RAM runs at 1002 MHz through a 384-bit bus. It also is made up of 512 SPUs, 64 Texture Address Units, and 48 Raster Operation Units.
Compare all of that to the Radeon HD 7970, which comes with core speeds of 925 MHz on the GPU, and 1375 MHz on the 3072 MB of GDDR5 memory. It features 2048 SPUs along with 128 TAUs and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 7970 should perform quite a bit faster than the GeForce GTX 580 overall. (explain)
Texel RateThe Radeon HD 7970 should be quite a bit (approximately 140%) better at AF than the GeForce GTX 580. (explain)
Pixel RateThe GeForce GTX 580 is much (more or less 25%) faster with regards to AA than the Radeon HD 7970, and will 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: Bandwidth is the maximum amount of data (measured in megabytes per second) that can be transported across the external memory interface in one second. It's calculated by multiplying the bus width by its memory speed. If the card has DDR RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed per second. This number is calculated by multiplying the total amount of texture units by the core speed of the chip. The higher this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.
Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card could possibly record to its local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the number of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate also depends on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.