Compare any two graphics cards:
Radeon HD 7850 vs Radeon HD 7970
IntroThe Radeon HD 7850 features a GPU core clock speed of 860 MHz, and the 2048 MB of GDDR5 memory runs at 1200 MHz through a 256-bit bus. It also is made up of 1024 SPUs, 64 Texture Address Units, and 32 Raster Operation Units.
Compare all that to the Radeon HD 7970, which comes with GPU core 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 Stream Processors, 128 Texture Address Units, and 32 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 7970, in theory, should perform a lot faster than the Radeon HD 7850 overall. (explain)
Texel RateThe Radeon HD 7970 should be quite a bit (about 115%) faster with regards to AF than the Radeon HD 7850. (explain)
Pixel RateThe Radeon HD 7970 should be just a bit (more or less 8%) better at AA than the Radeon HD 7850, and 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: Bandwidth is the largest amount of data (counted in MB per second) that can be transported past the external memory interface in one second. It's calculated by multiplying the bus width by its memory clock speed. If the card has DDR type memory, it must be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen 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 texture units by the core speed of the chip. The better the texel rate, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.
Pixel Rate: Pixel rate is the maximum number of pixels the graphics card could possibly record to the local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of colour ROPs by the clock 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 output rate is also dependant on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.