Compare any two graphics cards:
Radeon HD 6950 vs Radeon HD 7950
IntroThe Radeon HD 6950 comes with core clock speeds of 800 MHz on the GPU, and 1250 MHz on the 1024 MB of GDDR5 RAM. It features 1408 SPUs along with 88 TAUs and 32 Rasterization Operator Units.
Compare those specs to the Radeon HD 7950, which uses a 28 nm design. AMD has set the core speed at 800 MHz. The GDDR5 RAM works at a frequency of 1250 MHz on this specific card. It features 1792 SPUs along with 112 Texture Address Units and 32 ROPs.
Power Usage and Theoretical BenchmarksBoth cards have the same power consumption.
Theoretically speaking, the Radeon HD 7950 is 50% faster than the Radeon HD 6950 in general, because of its higher data rate. (explain)
Texel RateThe Radeon HD 7950 will be a lot (about 27%) faster with regards to AF than the Radeon HD 6950. (explain)
Pixel RateBoth cards have exactly the same pixel fill rate, so theoretically they should perform equally good at at FSAA, and be able to handle the same screen resolutions. (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 max amount of data (in units of megabytes per second) that can be moved across the external memory interface in a second. It's calculated by multiplying the card's bus width by its memory clock speed. If the card has DDR memory, it must be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the bandwidth is, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed in one second. This is worked out by multiplying the total number of texture units by the core clock speed of the chip. The higher the texel rate, the better the video 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 most pixels the video card can possibly write to the local memory in a second - measured in millions of pixels per second. The number is worked out by multiplying the amount of ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends on quite a few other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.