Compare any two graphics cards:
Radeon HD 6790 vs Radeon HD 7950
IntroThe Radeon HD 6790 comes with a GPU clock speed of 840 MHz, and the 1024 MB of GDDR5 RAM runs at 1050 MHz through a 256-bit bus. It also features 800 Stream Processors, 40 Texture Address Units, and 16 ROPs.
Compare all that to the Radeon HD 7950, which uses a 28 nm design. AMD has set the core speed at 800 MHz. The GDDR5 memory runs at a speed of 1250 MHz on this card. It features 1792 SPUs as well as 112 Texture Address Units and 32 Rasterization Operator Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 7950 will be 79% quicker than the Radeon HD 6790 overall, due to its higher bandwidth. (explain)
Texel RateThe Radeon HD 7950 is much (more or less 167%) better at anisotropic filtering than the Radeon HD 6790. (explain)
Pixel RateIf using a high resolution is important to you, then the Radeon HD 7950 is superior to the Radeon HD 6790, 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: Bandwidth is the largest amount of information (measured in megabytes per second) that can be moved over the external memory interface in a second. The number is calculated by multiplying the card's interface width by its memory speed. If it uses DDR RAM, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the better the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that can be applied per second. This figure is calculated by multiplying the total amount of texture units by the core speed of the chip. The higher this number, the better the 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 maximum number of pixels that the graphics card could possibly write to the local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the number of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate is also dependant on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.