Compare any two graphics cards:
Radeon HD 7990 vs Radeon R9 290X
IntroThe Radeon HD 7990 uses a 28 nm design. AMD has set the core speed at 950 MHz. The GDDR5 RAM is set to run at a frequency of 1500 MHz on this specific card. It features 2048 SPUs as well as 128 TAUs and 32 Rasterization Operator Units.
Compare all that to the Radeon R9 290X, which has a core clock frequency of 800 MHz and a GDDR5 memory speed of 1250 MHz. It also uses a 512-bit memory bus, and uses a 28 nm design. It is comprised of 2816 SPUs, 176 TAUs, and 64 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 7990 will be 80% faster than the Radeon R9 290X overall, because of its greater bandwidth. (explain)
Texel RateThe Radeon HD 7990 is quite a bit (approximately 73%) faster with regards to texture filtering than the Radeon R9 290X. (explain)
Pixel RateThe Radeon HD 7990 is a bit (more or less 19%) better at AA than the Radeon R9 290X, and will be capable of handling higher 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.
One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.
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 information (measured in MB per second) that can be transported across the external memory interface in one second. It's calculated by multiplying the bus width by its memory speed. If it uses DDR memory, the result should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the card's memory bandwidth, the faster 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 can be processed in one second. This figure is worked out by multiplying the total texture units by the core speed of the chip. The higher this number, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.
Pixel Rate: Pixel rate is the most pixels the video card could possibly write to the local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes 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, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.