Compare any two graphics cards:
Radeon HD 5970 vs Radeon HD 6990
IntroThe Radeon HD 5970 features core speeds of 725 MHz on the GPU, and 1000 MHz on the 1024 MB of GDDR5 RAM. It features 1600 SPUs as well as 160 Texture Address Units and 64 ROPs.
Compare that to the Radeon HD 6990, which makes use of a 40 nm design. AMD has set the core speed at 830 MHz. The GDDR5 RAM runs at a frequency of 1250 MHz on this particular model. It features 1536 SPUs along with 96 TAUs and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 6990 should theoretically be quite a bit faster than the Radeon HD 5970 overall. (explain)
Texel RateThe Radeon HD 5970 should be much (more or less 46%) more effective at anisotropic filtering than the Radeon HD 6990. (explain)
Pixel RateThe Radeon HD 5970 should be quite a bit (more or less 75%) faster with regards to FSAA than the Radeon HD 6990, and will be capable of handling higher screen resolutions without losing too much performance. (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: Memory bandwidth is the max amount of data (measured in MB per second) that can be moved past the external memory interface within a second. It's worked out by multiplying the card's bus width by its memory speed. If it uses DDR memory, the result should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that can be applied in one second. This figure is worked out by multiplying the total number of texture units by the core speed of the chip. The better the texel rate, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip can possibly write to its local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the amount of colour 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 output rate also depends on lots of other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.