Compare any two graphics cards:
Radeon HD 5830 vs Radeon HD 6850
IntroThe Radeon HD 5830 uses a 40 nm design. AMD has clocked the core frequency at 800 MHz. The GDDR5 RAM works at a speed of 1000 MHz on this specific card. It features 1120(224x5) SPUs as well as 56 Texture Address Units and 16 Rasterization Operator Units.
Compare all that to the Radeon HD 6850, which makes use of a 40 nm design. AMD has set the core frequency at 775 MHz. The GDDR5 memory works at a frequency of 1000 MHz on this specific card. It features 960 SPUs along with 48 Texture Address Units and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Both cards have exactly the same bandwidth, so theoretically they should have the same performance. (explain)
Texel RateThe Radeon HD 5830 should be a bit (approximately 20%) more effective at AF than the Radeon HD 6850. (explain)
Pixel RateIf running with lots of anti-aliasing 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 (in units of megabytes per second) that can be moved over the external memory interface in a second. The number is calculated by multiplying the bus width by its memory clock speed. If the card has DDR type RAM, the result should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher 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 amount of texture map elements (texels) that can be applied per second. This is calculated by multiplying the total texture units by the core speed of the chip. The higher the texel rate, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.
Pixel Rate: Pixel rate is the maximum amount of pixels the video card could possibly write to the local memory in a second - measured in millions of pixels per second. The number is worked out by multiplying the amount of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate is also dependant on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.