Compare any two graphics cards:
Radeon HD 7770 vs Radeon R7 250
IntroThe Radeon HD 7770 comes with a core clock frequency of 1000 MHz and a GDDR5 memory frequency of 1125 MHz. It also makes use of a 128-bit bus, and makes use of a 28 nm design. It features 640 SPUs, 40 TAUs, and 16 ROPs.
Compare those specs to the Radeon R7 250, which comes with a core clock speed of 1000 MHz and a GDDR5 memory frequency of 1150 MHz. It also makes use of a 128-bit memory bus, and makes use of a 28 nm design. It is made up of 384 SPUs, 24 TAUs, and 8 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon R7 250 will be 2% quicker than the Radeon HD 7770 overall, because of its higher data rate. (explain)
Texel RateThe Radeon HD 7770 should be much (approximately 67%) faster with regards to anisotropic filtering than the Radeon R7 250. (explain)
Pixel RateIf running with lots of anti-aliasing is important to you, then the Radeon HD 7770 is the winner, by a large margin. (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 (counted in megabytes per second) that can be transported past the external memory interface in one second. It's calculated by multiplying the bus width by its memory clock speed. If it uses DDR RAM, it should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the bandwidth is, 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 texture map elements (texels) that can be processed in one second. This number is worked out by multiplying the total texture units of the card by the core speed of the chip. The higher this number, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip could possibly write to the local memory per second - measured in millions of pixels per second. The number is calculated by multiplying the amount of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate also depends on many other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.