Compare any two graphics cards:
Radeon HD 5770 vs Radeon HD 6850
IntroThe Radeon HD 5770 has a core clock speed of 850 MHz and a GDDR5 memory frequency of 1200 MHz. It also features a 128-bit memory bus, and makes use of a 40 nm design. It is made up of 800(160x5) SPUs, 40 TAUs, and 16 Raster Operation Units.
Compare all of that to the Radeon HD 6850, which comes with a clock frequency of 775 MHz and a GDDR5 memory speed of 1000 MHz. It also makes use of a 256-bit bus, and uses a 40 nm design. It is made up of 960 SPUs, 48 Texture Address Units, and 32 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 6850 is 67% quicker than the Radeon HD 5770 in general, due to its greater data rate. (explain)
Texel RateThe Radeon HD 6850 will be a bit (about 9%) more effective at AF than the Radeon HD 5770. (explain)
Pixel RateIf running with a high screen resolution is important to you, then the Radeon HD 6850 is superior to the Radeon HD 5770, 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: Memory bandwidth is the largest amount of data (counted in MB per second) that can be moved past the external memory interface within a second. It is worked out by multiplying the interface width by its memory clock speed. If it uses DDR memory, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be applied per second. This is calculated by multiplying the total number of texture units by the core speed of the chip. The higher the texel rate, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card could possibly write to the local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the number 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 fill rate is also dependant on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.