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 set the core speed at 840 MHz. The GDDR5 RAM is set to run at a speed of 1050 MHz on this particular card. It features 800 SPUs as well as 40 Texture Address Units and 16 ROPs.
Compare those specs to the Radeon HD 7770, which uses a 28 nm design. AMD has set the core speed at 1000 MHz. The GDDR5 memory works at a speed of 1125 MHz on this specific card. 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)
In theory, the Radeon HD 6790 will be 87% faster than the Radeon HD 7770 overall, due to its greater bandwidth. (explain)
Texel RateThe Radeon HD 7770 will be a little bit (more or less 19%) better at AF than the Radeon HD 6790. (explain)
Pixel RateIf running with high levels of AA is important to you, then the Radeon HD 7770 is a better choice, but it probably won't make a huge difference. (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: Memory bandwidth is the maximum amount of data (in units of MB per second) that can be transported across the external memory interface in one second. The number is calculated by multiplying the interface width by its memory clock speed. If it uses DDR type memory, the result 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, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are processed in one second. This figure is worked out by multiplying the total amount of texture units by the core speed of the chip. The higher this number, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.
Pixel Rate: Pixel rate is the most pixels the video card can possibly write to its local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the number of ROPs by the the core 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, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to get to the max fill rate.