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 frequency at 950 MHz. The GDDR5 memory is set to run at a speed of 1500 MHz on this particular card. It features 2048 SPUs along with 128 TAUs and 32 Rasterization Operator Units.
Compare that to the Radeon R9 290X, which comes with a core clock frequency of 800 MHz and a GDDR5 memory frequency of 1250 MHz. It also features a 512-bit memory bus, and makes use of a 28 nm design. It is made up of 2816 SPUs, 176 TAUs, and 64 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 7990 should in theory perform much faster than the Radeon R9 290X in general. (explain)
Texel RateThe Radeon HD 7990 should be a lot (about 73%) better at texture filtering than the Radeon R9 290X. (explain)
Pixel RateThe Radeon HD 7990 should be a little bit (approximately 19%) faster with regards to AA than the Radeon R9 290X, and should be capable of handling higher screen resolutions while still performing well. (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 max amount of information (counted in megabytes per second) that can be transported past the external memory interface in a second. It is worked out by multiplying the interface width by its memory clock speed. If the card has DDR type memory, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be applied per second. This number is worked out by multiplying the total texture units by the core speed of the chip. The higher the texel rate, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card could possibly record to the local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of Raster Operations Pipelines by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate also depends on many other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the maximum fill rate.