Compare any two graphics cards:
Radeon HD 7870 XT vs Radeon R9 270X
IntroThe Radeon HD 7870 XT comes with clock speeds of 925 MHz on the GPU, and 1500 MHz on the 2048 MB of GDDR5 RAM. It features 1536 SPUs along with 96 Texture Address Units and 32 Rasterization Operator Units.
Compare those specs to the Radeon R9 270X, which features a GPU core clock speed of 1000 MHz, and 2048 MB of GDDR5 memory running at 1400 MHz through a 256-bit bus. It also is made up of 1280 SPUs, 80 TAUs, and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 7870 XT should be 7% faster than the Radeon R9 270X in general, due to its higher bandwidth. (explain)
Texel RateThe Radeon HD 7870 XT should be a bit (about 11%) faster with regards to anisotropic filtering than the Radeon R9 270X. (explain)
Pixel RateThe Radeon R9 270X is a small bit (about 8%) better at anti-aliasing than the Radeon HD 7870 XT, and will be capable of handling higher resolutions more effectively. (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 MB per second) that can be transported across the external memory interface within a second. It's worked out by multiplying the bus width by its memory clock speed. In the case of DDR type RAM, the result should be multiplied by 2 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 number of texture map elements (texels) that can be applied per second. This figure is calculated by multiplying the total amount of texture units by the core speed of the chip. The better the texel rate, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip could possibly write to its local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the number of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate also depends 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.