Compare any two graphics cards:
Radeon HD 6950 vs Radeon HD 7850
IntroThe Radeon HD 6950 comes with core speeds of 800 MHz on the GPU, and 1250 MHz on the 1024 MB of GDDR5 memory. It features 1408 SPUs along with 88 Texture Address Units and 32 ROPs.
Compare those specifications to the Radeon HD 7850, which comes with a clock frequency of 860 MHz and a GDDR5 memory speed of 1200 MHz. It also uses a 256-bit memory bus, and makes use of a 28 nm design. It is comprised of 1024 SPUs, 64 Texture Address Units, and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the Radeon HD 6950 should in theory be a little bit superior to the Radeon HD 7850 overall. (explain)
Texel RateThe Radeon HD 6950 will be quite a bit (about 28%) more effective at AF than the Radeon HD 7850. (explain)
Pixel RateIf using a high resolution is important to you, then the Radeon HD 7850 is superior to the Radeon HD 6950, though only just barely. (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 max amount of data (in units of megabytes per second) that can be moved over the external memory interface in a second. It is worked out by multiplying the card's bus width by its memory speed. If the card has DDR type RAM, the result should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are applied in one second. This figure is calculated by multiplying the total texture units of the card by the core speed of the chip. The higher this number, the better the graphics 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 amount of pixels that the graphics chip can possibly write to its local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the number of Render Output Units by the the core 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 fill rate is also dependant on lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the max fill rate.