Compare any two graphics cards:
Radeon HD 6950 2GB vs Radeon HD 7950 3GB
IntroThe Radeon HD 6950 2GB features a clock frequency of 800 MHz and a GDDR5 memory speed of 1250 MHz. It also makes use of a 256-bit bus, and makes use of a 40 nm design. It is comprised of 1408 SPUs, 88 Texture Address Units, and 32 Raster Operation Units.
Compare those specs to the Radeon HD 7950 3GB, which has a core clock frequency of 800 MHz and a GDDR5 memory frequency of 1250 MHz. It also makes use of a 384-bit memory bus, and makes use of a 28 nm design. It is made up of 1792 SPUs, 112 Texture Address Units, and 32 ROPs.
Power Usage and Theoretical BenchmarksBoth cards have the same power consumption.
As far as performance goes, the Radeon HD 7950 3GB should in theory be a lot superior to the Radeon HD 6950 2GB in general. (explain)
Texel RateThe Radeon HD 7950 3GB is a lot (more or less 27%) more effective at AF than the Radeon HD 6950 2GB. (explain)
Pixel RateBoth cards have exactly the same pixel fill rate, so theoretically they should be equally good at at FSAA, and be able to handle the same 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: Bandwidth is the largest amount of data (measured in MB per second) that can be transported over the external memory interface within a second. It is calculated by multiplying the card's interface width by its memory clock speed. If the card has DDR memory, it must 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 AA, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed in one second. This is calculated by multiplying the total texture units of the card by the core speed of the chip. The better this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip can possibly record to its local memory per second - measured in millions of pixels per second. The number is calculated by multiplying the number of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate is also dependant on lots of other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.