Compare any two graphics cards:
Geforce GTX 770 vs Radeon HD 7990
IntroThe Geforce GTX 770 comes with a core clock speed of 1046 MHz and a GDDR5 memory speed of 1753 MHz. It also features a 256-bit bus, and uses a 28 nm design. It features 1536 SPUs, 128 TAUs, and 32 Raster Operation Units.
Compare those specs to the Radeon HD 7990, which has core speeds of 950 MHz on the GPU, and 1500 MHz on the 3072 MB of GDDR5 RAM. It features 2048 SPUs as well as 128 Texture Address Units and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the Radeon HD 7990 should in theory be a lot superior to the Geforce GTX 770 overall. (explain)
Texel RateThe Radeon HD 7990 should be much (about 82%) faster with regards to texture filtering than the Geforce GTX 770. (explain)
Pixel RateIf running with a high screen resolution is important to you, then the Radeon HD 7990 is superior to the Geforce GTX 770, by far. (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 (counted in MB per second) that can be transported past the external memory interface in one second. It is calculated by multiplying the interface width by its memory clock speed. If it uses DDR type memory, it must be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be processed in one second. This figure is calculated by multiplying the total number of texture units of the card by the core clock speed of the chip. The better this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.
Pixel Rate: Pixel rate is the most pixels the video card can possibly write to its local memory in a second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends on lots of other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.