Compare any two graphics cards:
Radeon HD 6970 vs Radeon HD 7970
IntroThe Radeon HD 6970 has a core clock speed of 880 MHz and a GDDR5 memory speed of 1375 MHz. It also uses a 256-bit memory bus, and uses a 40 nm design. It is made up of 1536 SPUs, 96 Texture Address Units, and 32 ROPs.
Compare all that to the Radeon HD 7970, which makes use of a 28 nm design. AMD has clocked the core frequency at 925 MHz. The GDDR5 memory runs at a frequency of 1375 MHz on this specific card. It features 2048 SPUs as well as 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.
Theoretically speaking, the Radeon HD 7970 is 50% quicker than the Radeon HD 6970 overall, because of its higher data rate. (explain)
Texel RateThe Radeon HD 7970 is quite a bit (approximately 40%) better at texture filtering than the Radeon HD 6970. (explain)
Pixel RateThe Radeon HD 7970 should be just a bit (about 5%) more effective at anti-aliasing than the Radeon HD 6970, and also capable of handling higher screen resolutions while still performing well. (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 data (counted in MB per second) that can be transferred across the external memory interface in one second. The number is calculated by multiplying the card's bus width by the speed of its memory. In the case of DDR memory, it should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher 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 applied in one second. This is worked out by multiplying the total number of texture units by the core clock speed of the chip. The higher this number, the better the 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 most pixels the video card can possibly write to the local memory in a second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as 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, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.