Compare any two graphics cards:
Radeon HD 6850 vs Radeon HD 6870
IntroThe Radeon HD 6850 features a core clock speed of 775 MHz and a GDDR5 memory speed of 1000 MHz. It also features a 256-bit bus, and uses a 40 nm design. It features 960 SPUs, 48 Texture Address Units, and 32 ROPs.
Compare that to the Radeon HD 6870, which comes with a GPU core clock speed of 900 MHz, and 1024 MB of GDDR5 memory running at 1050 MHz through a 256-bit bus. It also features 1120 Stream Processors, 56 Texture Address Units, and 32 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Performance-wise, the Radeon HD 6870 should theoretically be a bit superior to the Radeon HD 6850 in general. (explain)
Texel RateThe Radeon HD 6870 should be a lot (about 35%) more effective at AF than the Radeon HD 6850. (explain)
Pixel RateIf using a high resolution is important to you, then the Radeon HD 6870 is the winner, but only just. (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 (measured in megabytes per second) that can be transferred past the external memory interface within a second. It is calculated by multiplying the interface width by its memory speed. In the case of DDR RAM, it should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the bandwidth is, 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 number of texture map elements (texels) that can be processed per second. This figure is worked out by multiplying the total amount of texture units by the core speed of the chip. The higher this number, the better the 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 maximum amount of pixels the graphics card could possibly write to its local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the amount of Raster Operations Pipelines by the clock speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate is also dependant on quite a few other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.