Compare any two graphics cards:
Radeon HD 7850 vs Radeon R9 M390X
IntroThe Radeon HD 7850 comes with a core clock speed of 860 MHz and a GDDR5 memory frequency of 1200 MHz. It also features a 256-bit bus, and uses a 28 nm design. It is comprised of 1024 SPUs, 64 TAUs, and 32 ROPs.
Compare all that to the Radeon R9 M390X, which features a core clock frequency of 723 MHz and a GDDR5 memory speed of 1250 MHz. It also features a 256-bit bus, and makes use of a 28 nm design. It is made up of 2048 SPUs, 128 TAUs, and 32 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Performance-wise, the Radeon R9 M390X should theoretically be a small bit superior to the Radeon HD 7850 in general. (explain)
Texel RateThe Radeon R9 M390X will be quite a bit (approximately 68%) faster with regards to texture filtering than the Radeon HD 7850. (explain)
Pixel RateIf running with lots of anti-aliasing is important to you, then the Radeon HD 7850 is a better choice, though only just barely. (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.
Memory Bandwidth: Memory bandwidth is the largest amount of information (in units of MB per second) that can be moved over the external memory interface within a second. The number is calculated by multiplying the bus width by its memory speed. If it uses DDR type RAM, it must be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the card's memory bandwidth, 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 calculated by multiplying the total texture units of the card by the core speed of the chip. The better this number, the better the video card will be at 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 graphics card could possibly record to the local memory per second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of ROPs by the the card's 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 is also dependant on quite a few other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the max fill rate.