Compare any two graphics cards:
Radeon HD 4790 vs Radeon R9 M385X
IntroThe Radeon HD 4790 comes with clock speeds of 600 MHz on the GPU, and 800 MHz on the 512 MB of GDDR5 memory. It features 640(128x5) SPUs as well as 32 TAUs and 16 ROPs.
Compare that to the Radeon R9 M385X, which comes with clock speeds of 1100 MHz on the GPU, and 1500 MHz on the 4096 MB of GDDR5 memory. It features 896 SPUs along with 56 Texture Address Units and 16 ROPs.
Power Usage and Theoretical Benchmarks
Theoretically speaking, the Radeon HD 4790 should be 7% quicker than the Radeon R9 M385X in general, because of its greater bandwidth. (explain)
Texel RateThe Radeon R9 M385X is quite a bit (more or less 221%) more effective at AF than the Radeon HD 4790. (explain)
Pixel RateThe Radeon R9 M385X will be quite a bit (more or less 83%) better at full screen anti-aliasing than the Radeon HD 4790, and also able to handle higher resolutions without losing too much performance. (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 information (in units of megabytes per second) that can be transferred across the external memory interface within a second. It's calculated by multiplying the interface width by the speed of its memory. If it uses DDR RAM, it must be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, 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 can be processed in one second. This figure is worked out by multiplying the total amount of texture units by the core clock speed of the chip. The higher the texel rate, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.
Pixel Rate: Pixel rate is the most pixels that the graphics card could possibly record to the local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of Render Output Units 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 output rate also depends on many other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the max fill rate.