Compare any two graphics cards:
GeForce GTX 580 vs Radeon HD 4850 512MB
IntroThe GeForce GTX 580 comes with 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 TAUs, and 48 Raster Operation Units.
Compare those specs to the Radeon HD 4850 512MB, which makes use of a 55 nm design. AMD has set the core frequency at 625 MHz. The GDDR3 memory runs at a speed of 993 MHz on this specific model. It features 800(160x5) SPUs along with 40 TAUs and 16 Rasterization Operator Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically, the GeForce GTX 580 should be a lot faster than the Radeon HD 4850 512MB overall. (explain)
Texel RateThe GeForce GTX 580 is a lot (approximately 98%) more effective at anisotropic filtering than the Radeon HD 4850 512MB. (explain)
Pixel RateThe GeForce GTX 580 is quite a bit (approximately 271%) faster with regards to anti-aliasing than the Radeon HD 4850 512MB, and able to handle higher screen 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 max amount of data (measured in MB per second) that can be transported over the external memory interface in a second. The number is worked out by multiplying the card's bus width by its memory clock speed. If it uses DDR RAM, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the memory bandwidth, 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 texture map elements (texels) that are processed in one second. This figure is worked out by multiplying the total texture units by the core clock speed of the chip. The higher the texel rate, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics card could possibly write to its local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the number of Raster Operations Pipelines by the the core speed of the card. 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 also depends on quite a few other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.