Compare any two graphics cards:
Radeon HD 4850 X2 1GB vs Radeon HD 5970
IntroThe Radeon HD 4850 X2 1GB uses a 55 nm design. AMD has set the core speed at 625 MHz. The GDDR3 RAM is set to run at a frequency of 993 MHz on this specific card. It features 800(160x5) SPUs as well as 40 Texture Address Units and 16 ROPs.
Compare those specs to the Radeon HD 5970, which comes with GPU core speed of 725 MHz, and 1024 MB of GDDR5 memory set to run at 1000 MHz through a 256-bit bus. It also features 1600 SPUs, 160 Texture Address Units, and 64 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 5970 should be 101% faster than the Radeon HD 4850 X2 1GB in general, because of its higher bandwidth. (explain)
Texel RateThe Radeon HD 5970 should be a lot (more or less 364%) better at anisotropic filtering than the Radeon HD 4850 X2 1GB. (explain)
Pixel RateIf running with lots of anti-aliasing is important to you, then the Radeon HD 5970 is the winner, and very much so. (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.
Memory Bandwidth: Memory bandwidth is the maximum amount of information (counted in MB per second) that can be transported across the external memory interface in one second. The number is worked out by multiplying the card's interface width by its memory speed. In the case of DDR type RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are processed in one second. This number is worked out by multiplying the total texture units of the card by the core speed of the chip. The higher the texel rate, the better the 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 maximum amount of pixels the video card can possibly record to the local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate also depends on quite a few other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.