Compare any two graphics cards:
GeForce GTX 980M vs Radeon R9 M390X
IntroThe GeForce GTX 980M comes with a GPU core clock speed of 1038 MHz, and the 4096 MB of GDDR5 RAM is set to run at 1000 MHz through a 256-bit bus. It also features 1536 Stream Processors, 96 Texture Address Units, and 64 ROPs.
Compare those specifications to the Radeon R9 M390X, which features core clock speeds of 723 MHz on the GPU, and 1250 MHz on the 4096 MB of GDDR5 memory. It features 2048 SPUs along with 128 TAUs and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon R9 M390X, in theory, should be a lot faster than the GeForce GTX 980M overall. (explain)
Texel RateThe GeForce GTX 980M is just a bit (more or less 8%) more effective at anisotropic filtering than the Radeon R9 M390X. (explain)
Pixel RateIf running with a high screen resolution is important to you, then the GeForce GTX 980M is the winner, 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.
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 megabytes per second) that can be moved past the external memory interface in a second. It is worked out by multiplying the card's bus width by its memory speed. In the case of DDR memory, it should be multiplied by 2 again. If it uses 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 high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are applied in one second. This figure is worked out by multiplying the total 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 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 record to its local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate is also dependant on lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.