Compare any two graphics cards:
Radeon HD 5870 vs Radeon HD 6870
IntroThe Radeon HD 5870 has a core clock speed of 850 MHz and a GDDR5 memory frequency of 1200 MHz. It also features a 256-bit memory bus, and uses a 40 nm design. It features 1600(320x5) SPUs, 80 TAUs, and 32 Raster Operation Units.
Compare all of that to the Radeon HD 6870, which makes use of a 40 nm design. AMD has clocked the core frequency at 900 MHz. The GDDR5 memory runs at a speed of 1050 MHz on this model. It features 1120 SPUs along with 56 Texture Address Units and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 5870 should in theory be a little bit faster than the Radeon HD 6870 overall. (explain)
Texel RateThe Radeon HD 5870 should be much (approximately 35%) better at anisotropic filtering than the Radeon HD 6870. (explain)
Pixel RateThe Radeon HD 6870 should be just a bit (about 6%) better at anti-aliasing than the Radeon HD 5870, and also will be able to handle higher screen resolutions without slowing down too much. (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 information (counted in megabytes per second) that can be transferred across the external memory interface in a second. The number is calculated by multiplying the bus width by the speed of its memory. If the card has DDR memory, it should be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the bandwidth is, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed per second. This is worked out by multiplying the total texture units of the card by the core speed of the chip. The better the texel rate, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card can possibly write to its local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the number of Raster Operations Pipelines by the the core speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate also depends on many other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.