Compare any two graphics cards:
Radeon HD 6950 vs Radeon HD 7970
IntroThe Radeon HD 6950 features clock speeds of 800 MHz on the GPU, and 1250 MHz on the 1024 MB of GDDR5 RAM. It features 1408 SPUs as well as 88 Texture Address Units and 32 Rasterization Operator Units.
Compare those specifications to the Radeon HD 7970, which features core clock speeds of 925 MHz on the GPU, and 1375 MHz on the 3072 MB of GDDR5 memory. It features 2048 SPUs as well as 128 TAUs and 32 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the Radeon HD 7970 should in theory be much better than the Radeon HD 6950 in general. (explain)
Texel RateThe Radeon HD 7970 will be quite a bit (approximately 68%) more effective at anisotropic filtering than the Radeon HD 6950. (explain)
Pixel RateIf using a high screen resolution is important to you, then the Radeon HD 7970 is a better choice, though not by far. (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 (measured in megabytes per second) that can be transferred across the external memory interface in a second. The number is worked out by multiplying the card's bus width by its memory speed. In the case of DDR type memory, it must be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the bandwidth is, 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 can be processed per second. This figure is calculated by multiplying the total texture units of the card by the core clock speed of the chip. The higher the texel rate, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.
Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card can possibly record to its local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate also depends on lots of other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the maximum fill rate.