Compare any two graphics cards:
GeForce GTX 480 vs Radeon HD 6850
IntroThe GeForce GTX 480 features a GPU clock speed of 700 MHz, and the 1536 MB of GDDR5 RAM runs at 924 MHz through a 384-bit bus. It also is made up of 480 Stream Processors, 60 Texture Address Units, and 48 ROPs.
Compare those specifications to the Radeon HD 6850, which comes with a clock frequency of 775 MHz and a GDDR5 memory frequency of 1000 MHz. It also uses a 256-bit bus, and makes use of a 40 nm design. It is made up of 960 SPUs, 48 TAUs, and 32 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the GeForce GTX 480 should perform quite a bit faster than the Radeon HD 6850 overall. (explain)
Texel RateThe GeForce GTX 480 should be a small bit (more or less 13%) more effective at AF than the Radeon HD 6850. (explain)
Pixel RateThe GeForce GTX 480 is a lot (about 35%) more effective at anti-aliasing than the Radeon HD 6850, and also will be able to handle higher resolutions more effectively. (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 data (counted in megabytes per second) that can be moved past the external memory interface in one second. The number is calculated by multiplying the interface width by the speed of its memory. If it uses DDR type RAM, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be processed in one second. This number is calculated by multiplying the total amount of texture units by the core clock speed of the chip. The better the texel rate, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics card can possibly write to the local memory per second - measured in millions of pixels per second. The number is calculated by multiplying the number of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate also depends on quite a few other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the max fill rate.