Compare any two graphics cards:
Radeon HD 7870 XT vs Radeon R9 270X
IntroThe Radeon HD 7870 XT comes with core clock speeds of 925 MHz on the GPU, and 1500 MHz on the 2048 MB of GDDR5 memory. It features 1536 SPUs as well as 96 TAUs and 32 Rasterization Operator Units.
Compare those specifications to the Radeon R9 270X, which features GPU core speed of 1000 MHz, and 2048 MB of GDDR5 memory running at 1400 MHz through a 256-bit bus. It also features 1280 Stream Processors, 80 TAUs, and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 7870 XT should be 7% quicker than the Radeon R9 270X in general, because of its higher data rate. (explain)
Texel RateThe Radeon HD 7870 XT is just a bit (more or less 11%) better at AF than the Radeon R9 270X. (explain)
Pixel RateIf running with high levels of AA is important to you, then the Radeon R9 270X is a better choice, but not 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 information (counted in megabytes per second) that can be transferred over the external memory interface within a second. It is worked out by multiplying the card's bus width by the speed of its memory. If it uses DDR type memory, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed per second. This is worked out by multiplying the total number of texture units by the core speed of the chip. The better the texel rate, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.
Pixel Rate: Pixel rate is the maximum number of pixels the graphics card can possibly record to its local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill 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 maximum fill rate.