Compare any two graphics cards:
Radeon HD 4870 X2 vs Radeon HD 5870
IntroThe Radeon HD 4870 X2 features a GPU core speed of 750 MHz, and the 1024 MB of GDDR5 RAM runs at 900 MHz through a 256-bit bus. It also features 800(160x5) Stream Processors, 40 TAUs, and 16 Raster Operation Units.
Compare those specifications to the Radeon HD 5870, which uses a 40 nm design. AMD has set the core speed at 850 MHz. The GDDR5 memory works at a speed of 1200 MHz on this card. It features 1600(320x5) SPUs as well as 80 Texture Address Units and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 4870 X2 is 50% faster than the Radeon HD 5870 overall, because of its greater data rate. (explain)
Texel RateThe Radeon HD 5870 is just a bit (about 13%) faster with regards to AF than the Radeon HD 4870 X2. (explain)
Pixel RateThe Radeon HD 5870 should be a bit (approximately 13%) better at full screen anti-aliasing than the Radeon HD 4870 X2, and should be able to handle higher resolutions better. (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.
Radeon HD 4870 X2
Radeon HD 5870
Memory Bandwidth: Bandwidth is the max amount of data (counted in MB per second) that can be transferred across the external memory interface in one second. It's calculated by multiplying the interface width by its memory clock speed. In the case of DDR type memory, the result should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, the faster 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 number of texture map elements (texels) that can be applied in one second. This number is calculated by multiplying the total amount of texture units by the core clock speed of the chip. The higher this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.
Pixel Rate: Pixel rate is the most pixels the video card could possibly write to its local memory in one second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of colour ROPs by the the card's 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 also depends on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.
Radeon HD 4870 X2
Radeon HD 5870