Compare any two graphics cards:
Geforce GTX 670 vs Radeon HD 7990
IntroThe Geforce GTX 670 features a clock speed of 915 MHz and a GDDR5 memory frequency of 1500 MHz. It also makes use of a 256-bit memory bus, and makes use of a 28 nm design. It is made up of 1344 SPUs, 112 TAUs, and 32 Raster Operation Units.
Compare those specs to the Radeon HD 7990, which features core speeds of 950 MHz on the GPU, and 1500 MHz on the 3072 MB of GDDR5 memory. It features 2048 SPUs along with 128 Texture Address Units and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 7990 should be 200% faster than the Geforce GTX 670 in general, due to its higher data rate. (explain)
Texel RateThe Radeon HD 7990 is quite a bit (about 137%) better at anisotropic filtering than the Geforce GTX 670. (explain)
Pixel RateIf using lots of anti-aliasing is important to you, then the Radeon HD 7990 is superior to the Geforce GTX 670, 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.
Geforce GTX 670
Radeon HD 7990
Memory Bandwidth: Memory bandwidth is the max amount of data (measured in megabytes per second) that can be transported past the external memory interface in a second. It is calculated by multiplying the card's bus width by the speed of its memory. In the case of DDR RAM, 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 better the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that can be applied in one second. This number is worked out by multiplying the total number of texture units of the card by the core clock speed of the chip. The higher this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in a second.
Pixel Rate: Pixel rate is the maximum number of pixels the video card could possibly write to its local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of Raster Operations Pipelines by the clock speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate also depends on quite a few other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to get to the max fill rate.
Geforce GTX 670
Radeon HD 7990