Compare any two graphics cards:
Radeon HD 7870 vs Radeon R9 270
IntroThe Radeon HD 7870 has clock speeds of 1000 MHz on the GPU, and 1200 MHz on the 2048 MB of GDDR5 RAM. It features 1280 SPUs as well as 80 Texture Address Units and 32 Rasterization Operator Units.
Compare all of that to the Radeon R9 270, which comes with a clock frequency of 900 MHz and a GDDR5 memory speed of 1400 MHz. It also makes use of a 256-bit bus, and makes use of a 28 nm design. It features 1280 SPUs, 80 TAUs, and 32 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon R9 270 will be 17% faster than the Radeon HD 7870 in general, because of its greater data rate. (explain)
Texel RateThe Radeon HD 7870 should be just a bit (approximately 11%) more effective at AF than the Radeon R9 270. (explain)
Pixel RateIf running with high levels of AA is important to you, then the Radeon HD 7870 is a better choice, but only just. (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 megabytes per second) that can be transferred over the external memory interface within a second. It's worked out by multiplying the card's bus width by its memory speed. If it uses DDR type memory, the result should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be processed per second. This is worked out by multiplying the total number of texture units of the card by the core clock 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 applied in one second.
Pixel Rate: Pixel rate is the most pixels the video 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 Raster Operations Pipelines by the the core speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate also depends on lots of other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.