Compare any two graphics cards:
Radeon HD 6950 vs Radeon HD 7970
IntroThe Radeon HD 6950 features a GPU core speed of 800 MHz, and the 1024 MB of GDDR5 RAM is set to run at 1250 MHz through a 256-bit bus. It also is made up of 1408 Stream Processors, 88 Texture Address Units, and 32 Raster Operation Units.
Compare those specifications to the Radeon HD 7970, which features a GPU core clock speed of 925 MHz, and 3072 MB of GDDR5 memory running at 1375 MHz through a 384-bit bus. It also is comprised of 2048 SPUs, 128 TAUs, and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 7970, in theory, should be quite a bit faster than the Radeon HD 6950 overall. (explain)
Texel RateThe Radeon HD 7970 should be a lot (approximately 68%) better at anisotropic filtering than the Radeon HD 6950. (explain)
Pixel RateThe Radeon HD 7970 will be a little bit (about 16%) better at anti-aliasing than the Radeon HD 6950, and should be able to handle higher resolutions without slowing down too much. (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 over the external memory interface in one second. It's calculated by multiplying the bus width by its memory clock speed. In the case of DDR type RAM, it should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, 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 can be applied per second. This number is calculated by multiplying the total number of texture units by the core speed of the chip. The better the texel rate, 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 number 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 worked out by multiplying the number of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the max fill rate.