Compare any two graphics cards:
Radeon HD 7770 vs Radeon HD 7850
IntroThe Radeon HD 7770 features a GPU clock speed of 1000 MHz, and the 1024 MB of GDDR5 memory runs at 1125 MHz through a 128-bit bus. It also is made up of 640 Stream Processors, 40 Texture Address Units, and 16 Raster Operation Units.
Compare those specs to the Radeon HD 7850, which has GPU clock speed of 860 MHz, and 2048 MB of GDDR5 memory set to run 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)
Performance-wise, the Radeon HD 7850 should in theory be a lot better than the Radeon HD 7770 overall. (explain)
Texel RateThe Radeon HD 7850 is quite a bit (about 38%) faster with regards to AF than the Radeon HD 7770. (explain)
Pixel RateThe Radeon HD 7850 is much (more or less 72%) faster with regards to anti-aliasing than the Radeon HD 7770, and also should be able to handle higher screen resolutions better. (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 (measured in MB per second) that can be moved past the external memory interface in one second. The number is worked out by multiplying the bus width by the speed of its memory. In the case of DDR RAM, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the 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 can be applied in one second. This figure is worked out by multiplying the total number of texture units by the core speed of the chip. The higher the texel rate, the better the graphics 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 its local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the amount of colour ROPs 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 rate is also dependant on many other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to get to the maximum fill rate.