Compare any two graphics cards:
Radeon HD 7870 XT vs Radeon R9 270X
IntroThe Radeon HD 7870 XT features a GPU core clock speed of 925 MHz, and the 2048 MB of GDDR5 RAM is set to run at 1500 MHz through a 256-bit bus. It also is made up of 1536 SPUs, 96 Texture Address Units, and 32 Raster Operation Units.
Compare all of that to the Radeon R9 270X, which features a clock speed of 1000 MHz and a GDDR5 memory frequency of 1400 MHz. It also uses a 256-bit memory bus, and uses a 28 nm design. It is comprised of 1280 SPUs, 80 Texture Address Units, and 32 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 7870 XT should theoretically perform a bit faster than the Radeon R9 270X overall. (explain)
Texel RateThe Radeon HD 7870 XT should be a bit (about 11%) better at texture filtering than the Radeon R9 270X. (explain)
Pixel RateIf using a high screen resolution is important to you, then the Radeon R9 270X is a better choice, though 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: Memory bandwidth is the largest amount of data (measured in MB per second) that can be transported over the external memory interface within a second. It's calculated by multiplying the card's bus width by its memory speed. In the case of DDR type RAM, the result should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be applied in one second. This number is calculated by multiplying the total amount of texture units of the card by the core speed of the chip. The higher the texel rate, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics card could possibly write to its local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate is also dependant on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the maximum fill rate.