Compare any two graphics cards:
Radeon HD 5870 vs Radeon HD 7970
IntroThe Radeon HD 5870 has a GPU core speed of 850 MHz, and the 1024 MB of GDDR5 memory runs at 1200 MHz through a 256-bit bus. It also is made up of 1600(320x5) Stream Processors, 80 TAUs, and 32 ROPs.
Compare those specs to the Radeon HD 7970, which makes use of a 28 nm design. AMD has set the core speed at 925 MHz. The GDDR5 memory runs at a speed of 1375 MHz on this particular model. It features 2048 SPUs as well as 128 TAUs and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the Radeon HD 7970 should in theory be quite a bit better than the Radeon HD 5870 in general. (explain)
Texel RateThe Radeon HD 7970 will be a lot (approximately 74%) better at anisotropic filtering than the Radeon HD 5870. (explain)
Pixel RateIf running with a high screen resolution is important to you, then the Radeon HD 7970 is superior to the Radeon HD 5870, but only just. (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 data (in units of megabytes per second) that can be transported past the external memory interface in a second. The number is worked out by multiplying the bus width by its memory speed. In the case of DDR memory, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the bandwidth is, the faster 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 applied per second. This is worked out by multiplying the total number of texture units by the core clock speed of the chip. The better this number, the better the video 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 number of pixels the video card could possibly write to its local memory per second - measured in millions of pixels per second. The number is calculated by multiplying the number of Render Output Units by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate is also dependant on lots of other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to get to the max fill rate.