Compare any two graphics cards:
GeForce GTX 580 vs Radeon HD 4850 512MB
IntroThe GeForce GTX 580 has a GPU core clock speed of 772 MHz, and the 1536 MB of GDDR5 RAM is set to run at 1002 MHz through a 384-bit bus. It also is comprised of 512 SPUs, 64 Texture Address Units, and 48 ROPs.
Compare those specs to the Radeon HD 4850 512MB, which has core speeds of 625 MHz on the GPU, and 993 MHz on the 512 MB of GDDR3 memory. It features 800(160x5) SPUs along with 40 TAUs and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The GeForce GTX 580 should theoretically perform quite a bit faster than the Radeon HD 4850 512MB in general. (explain)
Texel RateThe GeForce GTX 580 should be quite a bit (about 98%) more effective at texture filtering than the Radeon HD 4850 512MB. (explain)
Pixel RateThe GeForce GTX 580 should be quite a bit (about 271%) better at anti-aliasing than the Radeon HD 4850 512MB, and also able to handle 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.
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 largest amount of information (measured in MB per second) that can be transferred past the external memory interface within a second. It's calculated by multiplying the interface width by the speed of its memory. If the card has DDR type memory, it must be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the better the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum number 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 speed of the chip. The better this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.
Pixel Rate: Pixel rate is the maximum amount of pixels the video 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 colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate is also dependant on quite a few other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.