Compare any two graphics cards:
Radeon HD 6790 vs Radeon HD 7770
IntroThe Radeon HD 6790 features a GPU core clock speed of 840 MHz, and the 1024 MB of GDDR5 RAM is set to run at 1050 MHz through a 256-bit bus. It also features 800 SPUs, 40 TAUs, and 16 ROPs.
Compare that to the Radeon HD 7770, which has GPU clock speed of 1000 MHz, and 1024 MB of GDDR5 RAM set to run at 1125 MHz through a 128-bit bus. It also features 640 Stream Processors, 40 Texture Address Units, and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Performance-wise, the Radeon HD 6790 should in theory be much better than the Radeon HD 7770 overall. (explain)
Texel RateThe Radeon HD 7770 is a bit (about 19%) faster with regards to anisotropic filtering than the Radeon HD 6790. (explain)
Pixel RateThe Radeon HD 7770 should be just a bit (more or less 19%) faster with regards to full screen anti-aliasing than the Radeon HD 6790, and also 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: Memory bandwidth is the largest amount of data (in units of MB per second) that can be moved across the external memory interface within a second. It's calculated by multiplying the interface width by its memory speed. In the case of DDR type RAM, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the memory bandwidth, 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 number of texture map elements (texels) that are processed in one second. This is calculated by multiplying the total amount of texture units of the card by the core speed of the chip. The better the texel rate, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.
Pixel Rate: Pixel rate is the maximum number of pixels the graphics card could possibly record to its local memory per second - measured in millions of pixels per second. The number is calculated by multiplying the number of Render Output Units by the the card's clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends on many other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the max fill rate.