Compare any two graphics cards:
Radeon HD 6790 vs Radeon HD 7770
IntroThe Radeon HD 6790 has core clock speeds of 840 MHz on the GPU, and 1050 MHz on the 1024 MB of GDDR5 RAM. It features 800 SPUs as well as 40 TAUs and 16 Rasterization Operator Units.
Compare all that to the Radeon HD 7770, which uses a 28 nm design. AMD has clocked the core speed at 1000 MHz. The GDDR5 memory works at a speed of 1125 MHz on this particular card. It features 640 SPUs along with 40 Texture Address Units and 16 Rasterization Operator Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 6790 should be quite a bit faster than the Radeon HD 7770 in general. (explain)
Texel RateThe Radeon HD 7770 will be a bit (about 19%) more effective at anisotropic filtering than the Radeon HD 6790. (explain)
Pixel RateThe Radeon HD 7770 will be a little bit (more or less 19%) more effective at full screen anti-aliasing than the Radeon HD 6790, and also should be able to handle higher screen 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 max amount of information (measured in MB per second) that can be transferred across the external memory interface within a second. The number is worked out by multiplying the bus width by its memory clock speed. If the card has DDR memory, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the bandwidth is, the better the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed in one second. This number is worked out by multiplying the total amount of texture units of the card by the core clock speed of the chip. The higher this number, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.
Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card could possibly record to the local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the amount of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate is also dependant on many other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.