Compare any two graphics cards:
Radeon HD 7990 vs Radeon R9 290X
IntroThe Radeon HD 7990 has a GPU clock speed of 950 MHz, and the 3072 MB of GDDR5 RAM is set to run at 1500 MHz through a 384-bit bus. It also is made up of 2048 SPUs, 128 Texture Address Units, and 32 Raster Operation Units.
Compare those specifications to the Radeon R9 290X, which uses a 28 nm design. AMD has clocked the core speed at 800 MHz. The GDDR5 RAM runs at a speed of 1250 MHz on this card. It features 2816 SPUs as well as 176 TAUs and 64 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Performance-wise, the Radeon HD 7990 should in theory be much superior to the Radeon R9 290X in general. (explain)
Texel RateThe Radeon HD 7990 should be quite a bit (more or less 73%) better at texture filtering than the Radeon R9 290X. (explain)
Pixel RateThe Radeon HD 7990 is a little bit (approximately 19%) better at full screen anti-aliasing than the Radeon R9 290X, and also will be capable of handling higher screen 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.
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: Bandwidth is the maximum amount of data (measured in MB per second) that can be transported over the external memory interface in one second. The number is worked out by multiplying the card's bus width by its memory clock speed. If it uses DDR RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the better the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are applied per second. This number is worked out by multiplying the total amount of texture units by the core clock speed of the chip. The better the texel rate, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.
Pixel Rate: Pixel rate is the most pixels the graphics card can possibly write to its local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.