Compare any two graphics cards:
Radeon HD 5830 vs Radeon HD 6850
IntroThe Radeon HD 5830 features core speeds of 800 MHz on the GPU, and 1000 MHz on the 1024 MB of GDDR5 RAM. It features 1120(224x5) SPUs as well as 56 TAUs and 16 Rasterization Operator Units.
Compare that to the Radeon HD 6850, which comes with GPU core speed of 775 MHz, and 1024 MB of GDDR5 RAM set to run at 1000 MHz through a 256-bit bus. It also is comprised of 960 Stream Processors, 48 TAUs, and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Both cards have the exact same memory bandwidth, so in theory they should have identical performance. (explain)
Texel RateThe Radeon HD 5830 is just a bit (about 20%) better at texture filtering than the Radeon HD 6850. (explain)
Pixel RateIf using a high resolution is important to you, then the Radeon HD 6850 is a better choice, by far. (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 information (counted in megabytes per second) that can be transferred across the external memory interface in one second. It's worked out by multiplying the interface width by its memory clock speed. If the card has DDR type RAM, it must be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be processed per second. This number is worked out by multiplying the total texture units of the card by the core clock speed of the chip. The higher this number, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.
Pixel Rate: Pixel rate is the most pixels that the graphics card could possibly record to its local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the number of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate also depends on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.