Compare any two graphics cards:
Geforce GTX 770 vs Radeon HD 7990
IntroThe Geforce GTX 770 uses a 28 nm design. nVidia has set the core frequency at 1046 MHz. The GDDR5 memory is set to run at a frequency of 1753 MHz on this specific card. It features 1536 SPUs as well as 128 Texture Address Units and 32 Rasterization Operator Units.
Compare all of that to the Radeon HD 7990, which uses a 28 nm design. AMD has clocked the core speed at 950 MHz. The GDDR5 RAM works at a frequency of 1500 MHz on this specific model. It features 2048 SPUs as well as 128 Texture Address Units and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 7990 is 157% faster than the Geforce GTX 770 in general, due to its higher bandwidth. (explain)
Texel RateThe Radeon HD 7990 will be a lot (approximately 82%) more effective at texture filtering than the Geforce GTX 770. (explain)
Pixel RateThe Radeon HD 7990 is quite a bit (more or less 82%) better at FSAA than the Geforce GTX 770, and also will be 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.
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 max amount of data (in units of MB per second) that can be moved past the external memory interface in one second. It's calculated by multiplying the card's bus width by its memory clock speed. If the card has DDR memory, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the memory bandwidth, the better 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 number of texture map elements (texels) that are processed per second. This is calculated by multiplying the total amount of texture units by the core speed of the chip. The better the texel rate, the better the graphics 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 number of pixels the graphics card can possibly write to the local memory per second - measured in millions of pixels per second. The number is calculated by multiplying the number of Render Output Units 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 also depends on many other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.