Compare any two graphics cards:
Radeon HD 6970 vs Radeon HD 7950 3GB
IntroThe Radeon HD 6970 has a 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 Raster Operation Units.
Compare all of that to the Radeon HD 7950 3GB, which features a clock speed of 800 MHz and a GDDR5 memory speed of 1250 MHz. It also uses a 384-bit bus, and makes use of a 28 nm design. It is comprised of 1792 SPUs, 112 TAUs, and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 7950 3GB should be 36% faster than the Radeon HD 6970 in general, because of its higher data rate. (explain)
Texel RateThe Radeon HD 7950 3GB should be a small bit (more or less 6%) better at anisotropic filtering than the Radeon HD 6970. (explain)
Pixel RateThe Radeon HD 6970 should be just a bit (more or less 10%) faster with regards to anti-aliasing than the Radeon HD 7950 3GB, and also will be able to handle higher resolutions without losing too much performance. (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 (measured in megabytes per second) that can be transferred past the external memory interface in one second. The number is worked out by multiplying the card's bus width by its memory clock speed. If the card has DDR RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed per second. This is calculated by multiplying the total number of texture units by the core 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 applied in a second.
Pixel Rate: Pixel rate is the maximum amount of pixels the video card can possibly record to the local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the number of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate also depends on lots of other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.