Compare any two graphics cards:
Radeon HD 5870 vs Radeon HD 6870
IntroThe Radeon HD 5870 features a core clock frequency of 850 MHz and a GDDR5 memory frequency of 1200 MHz. It also makes use of a 256-bit memory bus, and uses a 40 nm design. It features 1600(320x5) SPUs, 80 Texture Address Units, and 32 Raster Operation Units.
Compare those specifications to the Radeon HD 6870, which has clock speeds of 900 MHz on the GPU, and 1050 MHz on the 1024 MB of GDDR5 memory. It features 1120 SPUs along with 56 TAUs and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 5870 should in theory perform a bit faster than the Radeon HD 6870 overall. (explain)
Texel RateThe Radeon HD 5870 should be a lot (approximately 35%) faster with regards to texture filtering than the Radeon HD 6870. (explain)
Pixel RateIf running with a high resolution is important to you, then the Radeon HD 6870 is a better choice, though only just barely. (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: Memory bandwidth is the maximum amount of data (counted in megabytes per second) that can be transferred across the external memory interface within a second. It is calculated by multiplying the card's interface width by its memory clock speed. If it uses DDR type memory, it must be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the bandwidth is, the faster the card will be in general. It especially helps with anti-aliasing, HDR 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 of the card by the core clock speed of the chip. The higher this number, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.
Pixel Rate: Pixel rate is the maximum amount of pixels the video card could possibly write to its local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the number of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate is also dependant on many other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to get to the maximum fill rate.