Compare any two graphics cards:
Radeon HD 6870 vs Radeon HD 7790
IntroThe Radeon HD 6870 features clock speeds of 900 MHz on the GPU, and 1050 MHz on the 1024 MB of GDDR5 RAM. It features 1120 SPUs along with 56 Texture Address Units and 32 ROPs.
Compare all of that to the Radeon HD 7790, which comes with a core clock frequency of 1000 MHz and a GDDR5 memory frequency of 1500 MHz. It also features a 128-bit bus, and makes use of a 28 nm design. It is comprised of 896 SPUs, 56 Texture Address Units, and 16 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 6870 should perform quite a bit faster than the Radeon HD 7790 in general. (explain)
Texel RateThe Radeon HD 7790 should be a little bit (about 11%) better at texture filtering than the Radeon HD 6870. (explain)
Pixel RateIf using lots of anti-aliasing is important to you, then the Radeon HD 6870 is the winner, by a large margin. (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 MB per second) that can be transferred over the external memory interface within a second. It is worked out by multiplying the card's interface width by its memory speed. If it uses DDR memory, it should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, the better the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are 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 a second.
Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card could possibly write to the local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the amount of ROPs by the the card's clock speed. 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, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.