Compare any two graphics cards:
Geforce GTX 690 vs Radeon HD 7970
IntroThe Geforce GTX 690 has core speeds of 915 MHz on the GPU, and 1502 MHz on the 2048 MB of GDDR5 RAM. It features 1536 SPUs along with 128 Texture Address Units and 32 ROPs.
Compare those specs to the Radeon HD 7970, which features a clock speed of 925 MHz and a GDDR5 memory frequency of 1375 MHz. It also uses a 384-bit bus, and uses a 28 nm design. It is made up of 2048 SPUs, 128 Texture Address Units, and 32 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Performance-wise, the Geforce GTX 690 should theoretically be much better than the Radeon HD 7970 in general. (explain)
Texel RateThe Geforce GTX 690 should be much (more or less 98%) faster with regards to AF than the Radeon HD 7970. (explain)
Pixel RateIf using lots of anti-aliasing is important to you, then the Geforce GTX 690 is superior to the Radeon HD 7970, by a large margin. (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 maximum amount of information (in units of megabytes per second) that can be transported past the external memory interface in one second. It's worked out by multiplying the card's bus width by its memory clock speed. If it uses DDR memory, it should be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the bandwidth is, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed per second. This figure is worked out by multiplying the total number of texture units of the card by the core clock speed of the chip. The higher the texel rate, 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 most pixels that the graphics chip can possibly write to the local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the amount of ROPs by the clock 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 rate is also dependant on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.