Compare any two graphics cards:
Radeon HD 7870 vs Radeon HD 7970
IntroThe Radeon HD 7870 comes with a GPU core speed of 1000 MHz, and the 2048 MB of GDDR5 memory runs at 1200 MHz through a 256-bit bus. It also is made up of 1280 SPUs, 80 Texture Address Units, and 32 ROPs.
Compare that to the Radeon HD 7970, which has a core clock frequency of 925 MHz and a GDDR5 memory frequency of 1375 MHz. It also uses a 384-bit bus, and uses a 28 nm design. It features 2048 SPUs, 128 TAUs, and 32 Raster Operation Units.
(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 7870 in general. (explain)
Texel RateThe Radeon HD 7970 should be quite a bit (about 48%) better at anisotropic filtering than the Radeon HD 7870. (explain)
Pixel RateIf running with lots of anti-aliasing is important to you, then the Radeon HD 7870 is a better choice, but it probably won't make a huge difference. (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 maximum amount of information (measured in MB per second) that can be transferred past the external memory interface within a second. It's calculated by multiplying the card's bus width by the speed of its memory. If it uses DDR memory, it must be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed per second. This number 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 card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.
Pixel Rate: Pixel rate is the most pixels the video card could possibly write to its local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of Render Output Units by the the core speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate also depends on many other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the max fill rate.