Compare any two graphics cards:
Radeon HD 7770 vs Radeon HD 7850
IntroThe Radeon HD 7770 comes with a GPU core clock speed of 1000 MHz, and the 1024 MB of GDDR5 RAM runs at 1125 MHz through a 128-bit bus. It also is comprised of 640 SPUs, 40 TAUs, and 16 Raster Operation Units.
Compare all that to the Radeon HD 7850, which has GPU core speed of 860 MHz, and 2048 MB of GDDR5 RAM running at 1200 MHz through a 256-bit bus. It also is made up of 1024 SPUs, 64 Texture Address Units, and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 7850, in theory, should be much faster than the Radeon HD 7770 in general. (explain)
Texel RateThe Radeon HD 7850 should be a lot (more or less 38%) faster with regards to anisotropic filtering than the Radeon HD 7770. (explain)
Pixel RateIf using lots of anti-aliasing is important to you, then the Radeon HD 7850 is a better choice, by far. (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 largest amount of data (in units of megabytes per second) that can be moved over the external memory interface within a second. It's calculated by multiplying the card's bus width by its memory clock speed. If the card has DDR memory, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, 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 texture map elements (texels) that are processed per second. This is calculated 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 processed in a second.
Pixel Rate: Pixel rate is the most pixels that the graphics chip could possibly record to its local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the amount of Raster Operations Pipelines 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 fill rate is also dependant on quite a few other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.