Compare any two graphics cards:
Radeon HD 6870 vs Radeon HD 7850
IntroThe Radeon HD 6870 comes with clock speeds of 900 MHz on the GPU, and 1050 MHz on the 1024 MB of GDDR5 RAM. It features 1120 SPUs as well as 56 Texture Address Units and 32 ROPs.
Compare all of that to the Radeon HD 7850, which has core clock speeds of 860 MHz on the GPU, and 1200 MHz on the 2048 MB of GDDR5 memory. It features 1024 SPUs as well as 64 TAUs and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the Radeon HD 7850 should in theory be a small bit better than the Radeon HD 6870 in general. (explain)
Texel RateThe Radeon HD 7850 will be a bit (more or less 9%) better at anisotropic filtering than the Radeon HD 6870. (explain)
Pixel RateIf running with lots of anti-aliasing is important to you, then the Radeon HD 6870 is superior to the Radeon HD 7850, but it probably won't make a huge difference. (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 maximum amount of information (measured in MB per second) that can be moved across the external memory interface in a second. The number is worked out by multiplying the card's bus width by the speed of its memory. If the card has DDR type RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are processed in one second. This figure is worked out by multiplying the total amount of texture units of the card by the core clock speed of the chip. The higher this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.
Pixel Rate: Pixel rate is the most pixels that the graphics chip can possibly write to its local memory in one second - measured in millions of pixels per second. The figure is worked out 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 lots of 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.