Compare any two graphics cards:
Radeon HD 7850 vs Radeon HD 7870
IntroThe Radeon HD 7850 features a core clock speed of 860 MHz and a GDDR5 memory frequency of 1200 MHz. It also uses a 256-bit bus, and uses a 28 nm design. It is made up of 1024 SPUs, 64 TAUs, and 32 Raster Operation Units.
Compare those specifications to the Radeon HD 7870, which makes use of a 28 nm design. AMD has set the core frequency at 1000 MHz. The GDDR5 memory runs at a speed of 1200 MHz on this specific model. It features 1280 SPUs along with 80 TAUs and 32 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Both cards have the exact same memory bandwidth, so in theory they should have the same performance. (explain)
Texel RateThe Radeon HD 7870 will be quite a bit (more or less 45%) more effective at anisotropic filtering than the Radeon HD 7850. (explain)
Pixel RateThe Radeon HD 7870 should be a small bit (about 16%) more effective at AA than the Radeon HD 7850, and also able to handle higher resolutions while still performing well. (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 transferred past the external memory interface in a second. It is worked out by multiplying the card's bus width by its memory speed. If the card has DDR memory, the result should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the card's memory bandwidth, the better the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed per second. This number is worked out by multiplying the total amount of texture units by the core clock 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 per second.
Pixel Rate: Pixel rate is the maximum amount of pixels the video card could possibly write to its local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the number of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate is also dependant on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.