Compare any two graphics cards:
Radeon HD 6790 vs Radeon HD 7770
IntroThe Radeon HD 6790 makes use of a 40 nm design. AMD has clocked the core speed at 840 MHz. The GDDR5 RAM runs at a speed of 1050 MHz on this specific card. It features 800 SPUs along with 40 TAUs and 16 Rasterization Operator Units.
Compare all that to the Radeon HD 7770, which makes use of a 28 nm design. AMD has clocked the core speed at 1000 MHz. The GDDR5 memory works at a frequency of 1125 MHz on this particular model. It features 640 SPUs as well as 40 TAUs and 16 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the Radeon HD 6790 should theoretically be quite a bit better than the Radeon HD 7770 in general. (explain)
Texel RateThe Radeon HD 7770 will be a little bit (about 19%) better at anisotropic filtering than the Radeon HD 6790. (explain)
Pixel RateThe Radeon HD 7770 should be a little bit (about 19%) faster with regards to full screen anti-aliasing than the Radeon HD 6790, and also able to handle higher screen resolutions more effectively. (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 maximum amount of information (in units of MB per second) that can be transferred across the external memory interface in a second. It is worked out by multiplying the interface width by its memory clock speed. In the case of DDR RAM, it should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, the faster the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be applied in one second. This figure is calculated by multiplying the total texture units of the card by the core clock speed of the chip. The better the texel rate, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.
Pixel Rate: Pixel rate is the most pixels that the graphics card could possibly write to the local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the number of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate also depends on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.