Compare any two graphics cards:
Radeon HD 5850 vs Radeon HD 7970
IntroThe Radeon HD 5850 has a GPU core speed of 725 MHz, and the 1024 MB of GDDR5 RAM is set to run at 1000 MHz through a 256-bit bus. It also is made up of 1440(288x5) SPUs, 72 Texture Address Units, and 32 ROPs.
Compare all that to the Radeon HD 7970, which features a core clock speed of 925 MHz and a GDDR5 memory frequency of 1375 MHz. It also makes use of a 384-bit bus, and makes use of a 28 nm design. It is comprised of 2048 SPUs, 128 TAUs, and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 7970, in theory, should perform a lot faster than the Radeon HD 5850 overall. (explain)
Texel RateThe Radeon HD 7970 is a lot (about 127%) better at AF than the Radeon HD 5850. (explain)
Pixel RateIf using high levels of AA is important to you, then the Radeon HD 7970 is superior to the Radeon HD 5850, by a large margin. (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 largest amount of information (in units of megabytes per second) that can be transported across the external memory interface in a second. It's calculated by multiplying the card's interface width by its memory speed. If the card has DDR RAM, the result should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the bandwidth is, the faster the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied per second. This is calculated by multiplying the total number of texture units by the core speed of the chip. The higher the texel rate, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.
Pixel Rate: Pixel rate is the most pixels the video card can possibly write to the local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of Raster Operations Pipelines by the clock speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate also depends on many other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.