Compare any two graphics cards:
Radeon HD 6870 vs Radeon HD 6950
IntroThe Radeon HD 6870 has a core clock frequency of 900 MHz and a GDDR5 memory frequency of 1050 MHz. It also makes use of a 256-bit bus, and makes use of a 40 nm design. It is comprised of 1120 SPUs, 56 TAUs, and 32 ROPs.
Compare all that to the Radeon HD 6950, which has a clock speed of 800 MHz and a GDDR5 memory speed of 1250 MHz. It also makes use of a 256-bit memory bus, and makes use of a 40 nm design. It is made up of 1408 SPUs, 88 TAUs, and 32 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 6950 is 19% faster than the Radeon HD 6870 in general, because of its greater data rate. (explain)
Texel RateThe Radeon HD 6950 should be a lot (approximately 40%) faster with regards to anisotropic filtering than the Radeon HD 6870. (explain)
Pixel RateThe Radeon HD 6870 should be a little bit (more or less 13%) better at FSAA than the Radeon HD 6950, and also should 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.
Radeon HD 6870
Radeon HD 6950
Memory Bandwidth: Bandwidth is the max amount of information (counted in megabytes per second) that can be transported past the external memory interface in one second. It's worked out by multiplying the card's interface width by the speed of its memory. If it uses DDR RAM, it must be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. 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 texture map elements (texels) that can be processed in one second. This number is worked out by multiplying the total texture units by the core clock speed of the chip. The higher this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in a second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip could possibly record to the local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the number of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate is also dependant on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to get to the max fill rate.
Radeon HD 6870
Radeon HD 6950