Compare any two graphics cards:
Radeon HD 5870 vs Radeon HD 7950
IntroThe Radeon HD 5870 uses a 40 nm design. AMD has clocked the core frequency at 850 MHz. The GDDR5 RAM works at a speed of 1200 MHz on this specific model. It features 1600(320x5) SPUs along with 80 Texture Address Units and 32 Rasterization Operator Units.
Compare that to the Radeon HD 7950, which features clock speeds of 800 MHz on the GPU, and 1250 MHz on the 1536 MB of GDDR5 RAM. It features 1792 SPUs along with 112 Texture Address Units and 32 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 7950 should be 56% faster than the Radeon HD 5870 overall, because of its greater data rate. (explain)
Texel RateThe Radeon HD 7950 should be much (about 32%) more effective at anisotropic filtering than the Radeon HD 5870. (explain)
Pixel RateThe Radeon HD 5870 is a little bit (more or less 6%) better at FSAA than the Radeon HD 7950, and will be able to handle higher screen resolutions without losing too much performance. (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: Bandwidth is the largest amount of information (counted in megabytes per second) that can be transferred over the external memory interface in a second. It is worked out by multiplying the card's interface width by the speed of its memory. In the case of DDR type memory, the result should be multiplied by 2 once again. If DDR5, multiply by 4 instead. 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 higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are processed per second. This number is worked out by multiplying the total texture units of the card by the core clock speed of the chip. The better this number, 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 amount of pixels the graphics card could possibly record to its local memory in a second - measured in millions of pixels per second. The figure is worked out 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 filling the screen with pixels (the image). The actual pixel output rate also depends 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 max fill rate.