Compare any two graphics cards:
Radeon HD 7770 vs Radeon R7 250
IntroThe Radeon HD 7770 has a GPU core speed of 1000 MHz, and the 1024 MB of GDDR5 RAM is set to run at 1125 MHz through a 128-bit bus. It also is comprised of 640 Stream Processors, 40 TAUs, and 16 Raster Operation Units.
Compare that to the Radeon R7 250, which comes with a clock speed of 1000 MHz and a GDDR5 memory frequency of 1150 MHz. It also uses a 128-bit bus, and uses a 28 nm design. It is comprised of 384 SPUs, 24 TAUs, and 8 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Performance-wise, the Radeon R7 250 should in theory be a small bit superior to the Radeon HD 7770 overall. (explain)
Texel RateThe Radeon HD 7770 will be quite a bit (about 67%) better at AF than the Radeon R7 250. (explain)
Pixel RateIf running with high levels of AA is important to you, then the Radeon HD 7770 is the winner, and very much so. (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 max amount of data (measured in megabytes 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 its memory speed. If the card has DDR type memory, it should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are processed in one second. This is calculated by multiplying the total texture units by the core clock speed of the chip. The better 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 maximum number of pixels that the graphics card could possibly write to the local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the number of Render Output Units 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 rate is also dependant on many other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.