Compare any two graphics cards:
Radeon HD 6970 vs Radeon HD 7970
IntroThe Radeon HD 6970 uses a 40 nm design. AMD has clocked the core speed at 880 MHz. The GDDR5 memory is set to run at a speed of 1375 MHz on this specific model. It features 1536 SPUs as well as 96 Texture Address Units and 32 ROPs.
Compare that to the Radeon HD 7970, which has a clock frequency of 925 MHz and a GDDR5 memory frequency of 1375 MHz. It also makes use of a 384-bit memory bus, and uses a 28 nm design. It is comprised of 2048 SPUs, 128 Texture Address Units, and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical BenchmarksBoth cards have the same power consumption.
As far as performance goes, the Radeon HD 7970 should in theory be a lot superior to the Radeon HD 6970 overall. (explain)
Texel RateThe Radeon HD 7970 should be a lot (more or less 40%) faster with regards to AF than the Radeon HD 6970. (explain)
Pixel RateIf using a high screen resolution is important to you, then the Radeon HD 7970 is a better choice, 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: Bandwidth is the max amount of information (in units of megabytes per second) that can be transferred over the external memory interface in a second. It is calculated by multiplying the card's bus width by the speed of its memory. If it uses DDR type RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed in one second. This number is calculated by multiplying the total texture units of the card by the core clock speed of the chip. The higher the texel rate, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in a second.
Pixel Rate: Pixel rate is the most pixels the graphics card could possibly record to the local memory in a second - measured in millions of pixels per second. The number is worked out by multiplying the amount of Render Output Units by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate is also dependant on quite a few other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the max fill rate.