Compare any two graphics cards:
Radeon HD 5870 vs Radeon HD 7950
IntroThe Radeon HD 5870 has a core clock speed of 850 MHz and a GDDR5 memory speed of 1200 MHz. It also uses a 256-bit bus, and makes use of a 40 nm design. It is made up of 1600(320x5) SPUs, 80 Texture Address Units, and 32 Raster Operation Units.
Compare that to the Radeon HD 7950, which comes with GPU clock speed of 800 MHz, and 1536 MB of GDDR5 memory set to run at 1250 MHz through a 384-bit bus. It also features 1792 Stream Processors, 112 TAUs, and 32 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 7950 should theoretically perform a lot faster than the Radeon HD 5870 overall. (explain)
Texel RateThe Radeon HD 7950 should be a lot (more or less 32%) better at texture filtering than the Radeon HD 5870. (explain)
Pixel RateThe Radeon HD 5870 is a little bit (more or less 6%) faster with regards to full screen anti-aliasing than the Radeon HD 7950, and also should be able to handle higher screen resolutions without slowing down too much. (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 max amount of data (counted in megabytes per second) that can be moved over the external memory interface within a second. It is worked out by multiplying the bus width by its memory speed. If it uses DDR type RAM, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed in one second. This is worked out by multiplying the total number of texture units of the card by the core speed of the chip. The better the texel rate, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.
Pixel Rate: Pixel rate is the maximum number of pixels the graphics card could possibly record to its local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of Render Output Units by the the core 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 is also dependant on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.