Compare any two graphics cards:
Radeon HD 6870 vs Radeon HD 7790
IntroThe Radeon HD 6870 features core speeds of 900 MHz on the GPU, and 1050 MHz on the 1024 MB of GDDR5 memory. It features 1120 SPUs as well as 56 Texture Address Units and 32 ROPs.
Compare that to the Radeon HD 7790, which makes use of a 28 nm design. AMD has set the core frequency at 1000 MHz. The GDDR5 memory works at a speed of 1500 MHz on this particular model. It features 896 SPUs along with 56 Texture Address Units and 16 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically, the Radeon HD 6870 should be a lot faster than the Radeon HD 7790 in general. (explain)
Texel RateThe Radeon HD 7790 will be a small bit (approximately 11%) better at anisotropic filtering than the Radeon HD 6870. (explain)
Pixel RateThe Radeon HD 6870 is a lot (approximately 80%) more effective at AA than the Radeon HD 7790, and also able to handle higher resolutions without slowing down too much. (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 (in units of MB per second) that can be moved over the external memory interface in a second. It is worked out by multiplying the interface width by its memory speed. If the card has DDR RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the memory bandwidth, the better the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed in one second. This figure is worked out by multiplying the total amount of texture units by the core speed of the chip. The better this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.
Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card could possibly record to its 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 - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. 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 reach the maximum fill rate.