Compare any two graphics cards:
Radeon HD 6950 vs Radeon HD 7970
IntroThe Radeon HD 6950 comes with a GPU clock speed of 800 MHz, and the 1024 MB of GDDR5 RAM runs at 1250 MHz through a 256-bit bus. It also features 1408 Stream Processors, 88 TAUs, and 32 Raster Operation Units.
Compare all of that to the Radeon HD 7970, which comes with GPU clock speed of 925 MHz, and 3072 MB of GDDR5 RAM set to run at 1375 MHz through a 384-bit bus. It also is comprised of 2048 Stream Processors, 128 Texture Address Units, and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the Radeon HD 7970 should theoretically be a lot better than the Radeon HD 6950 overall. (explain)
Texel RateThe Radeon HD 7970 will be much (about 68%) better at AF than the Radeon HD 6950. (explain)
Pixel RateThe Radeon HD 7970 is a bit (more or less 16%) more effective at full screen anti-aliasing than the Radeon HD 6950, and will be capable of handling higher 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: Memory bandwidth is the maximum amount of information (counted in megabytes per second) that can be moved over the external memory interface within a second. It is calculated by multiplying the card's interface width by the speed of its memory. In the case of DDR type memory, it must 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 higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed in one second. This number is calculated by multiplying the total number of texture units by the core speed of the chip. The higher this number, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.
Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card could possibly write to its local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of colour 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 fill rate is also dependant on quite a few other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the max fill rate.