Compare any two graphics cards:
GeForce GTX 580 vs Radeon HD 4850 512MB
IntroThe GeForce GTX 580 uses a 40 nm design. nVidia has set the core frequency at 772 MHz. The GDDR5 memory runs at a speed of 1002 MHz on this particular card. It features 512 SPUs as well as 64 TAUs and 48 ROPs.
Compare all of that to the Radeon HD 4850 512MB, which has a GPU core clock speed of 625 MHz, and 512 MB of GDDR3 RAM running at 993 MHz through a 256-bit bus. It also features 800(160x5) Stream Processors, 40 Texture Address Units, and 16 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the GeForce GTX 580 should be 203% faster than the Radeon HD 4850 512MB in general, because of its greater bandwidth. (explain)
Texel RateThe GeForce GTX 580 should be much (about 98%) faster with regards to AF than the Radeon HD 4850 512MB. (explain)
Pixel RateIf using a high screen resolution is important to you, then the GeForce GTX 580 is the winner, by far. (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 max amount of information (counted in MB per second) that can be moved over the external memory interface in one second. The number is worked out by multiplying the card's interface width by its memory clock speed. If the card has DDR type RAM, it should be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the memory bandwidth, the faster 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 can be applied in one second. This number is worked out by multiplying the total texture units by the core clock speed of the chip. The better 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 maximum number of pixels the video card can possibly record to its local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of ROPs by the clock 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 output rate is also dependant on many other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the maximum fill rate.