Compare any two graphics cards:
Radeon HD 6870 vs Radeon HD 7790
IntroThe Radeon HD 6870 has a clock frequency of 900 MHz and a GDDR5 memory speed of 1050 MHz. It also uses a 256-bit memory bus, and uses a 40 nm design. It features 1120 SPUs, 56 Texture Address Units, and 32 Raster Operation Units.
Compare those specs to the Radeon HD 7790, which has a GPU core clock speed of 1000 MHz, and 1024 MB of GDDR5 RAM running at 1500 MHz through a 128-bit bus. It also is comprised of 896 SPUs, 56 TAUs, and 16 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 6870 is 40% quicker than the Radeon HD 7790 in general, because of its higher bandwidth. (explain)
Texel RateThe Radeon HD 7790 will be just a bit (more or less 11%) faster with regards to texture filtering than the Radeon HD 6870. (explain)
Pixel RateThe Radeon HD 6870 should be a lot (approximately 80%) faster with regards to full screen anti-aliasing than the Radeon HD 7790, and also should be capable of handling higher screen resolutions better. (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 transported across the external memory interface in a second. It's worked out by multiplying the bus width by the speed of its memory. If it uses DDR RAM, the result should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be applied per second. This figure is worked out by multiplying the total texture units of the card by the core speed of the chip. The higher this number, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.
Pixel Rate: Pixel rate is the maximum number of pixels the graphics card can possibly record to the local memory in one second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate also depends on lots of other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.