Compare any two graphics cards:
Radeon HD 5970 vs Radeon HD 6990
IntroThe Radeon HD 5970 comes with a clock frequency of 725 MHz and a GDDR5 memory frequency of 1000 MHz. It also makes use of a 256-bit bus, and uses a 40 nm design. It is comprised of 1600 SPUs, 160 TAUs, and 64 Raster Operation Units.
Compare that to the Radeon HD 6990, which has a clock frequency of 830 MHz and a GDDR5 memory frequency of 1250 MHz. It also makes use of a 256-bit memory bus, and uses a 40 nm design. It features 1536 SPUs, 96 TAUs, and 32 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 6990 should perform much faster than the Radeon HD 5970 in general. (explain)
Texel RateThe Radeon HD 5970 is a lot (approximately 46%) better at texture filtering than the Radeon HD 6990. (explain)
Pixel RateThe Radeon HD 5970 should be much (more or less 75%) faster with regards to AA than the Radeon HD 6990, and should be able to handle higher resolutions while still performing well. (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.
One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.
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 (measured in megabytes per second) that can be moved across the external memory interface in a second. The number is worked out by multiplying the card's bus width by its memory clock speed. In the case of DDR type RAM, the result should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the bandwidth is, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are processed in one second. This number is calculated by multiplying the total amount of texture units by the core speed of the chip. The better the texel rate, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip could possibly record to the local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the amount of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate also depends on many other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to reach the maximum fill rate.