Compare any two graphics cards:
Radeon HD 6790 vs Radeon HD 7790
IntroThe Radeon HD 6790 comes with a GPU clock speed of 840 MHz, and the 1024 MB of GDDR5 memory runs at 1050 MHz through a 256-bit bus. It also features 800 Stream Processors, 40 Texture Address Units, and 16 Raster Operation Units.
Compare all that to the Radeon HD 7790, which makes use of a 28 nm design. AMD has clocked the core speed at 1000 MHz. The GDDR5 RAM is set to run at a frequency of 1500 MHz on this particular card. It features 896 SPUs as well as 56 Texture Address Units and 16 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 6790 should theoretically be quite a bit superior to the Radeon HD 7790 overall. (explain)
Texel RateThe Radeon HD 7790 should be quite a bit (more or less 67%) better at AF than the Radeon HD 6790. (explain)
Pixel RateThe Radeon HD 7790 will be a little bit (about 19%) more effective at AA than the Radeon HD 6790, 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: Bandwidth is the largest amount of information (measured in MB per second) that can be transported over the external memory interface in a second. It is calculated by multiplying the card's interface width by the speed of its memory. If the card has DDR RAM, it must be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the bandwidth is, the faster the card will be in general. It especially helps with AA, HDR and high 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 texture units by the core clock 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 in a second.
Pixel Rate: Pixel rate is the maximum amount of pixels the video card can possibly write to the local memory in a second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate also depends on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the max fill rate.