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 memory. It features 1280 SPUs along with 80 Texture Address Units and 32 Rasterization Operator Units.
Compare those specifications to the Radeon R9 270, which has GPU clock speed of 900 MHz, and 2048 MB of GDDR5 memory set to run at 1400 MHz through a 256-bit bus. It also features 1280 Stream Processors, 80 Texture Address Units, and 32 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon R9 270 should theoretically be just a bit faster than the Radeon HD 7870 overall. (explain)
Texel RateThe Radeon HD 7870 is just a bit (about 11%) faster with regards to anisotropic filtering 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, 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 maximum amount of information (in units of megabytes per second) that can be transported over the external memory interface in one second. It is worked out by multiplying the card's bus width by its memory speed. If the card has DDR type memory, the result should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, 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 can be processed per second. This number is calculated by multiplying the total texture units of the card by the core clock 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 applied in one second.
Pixel Rate: Pixel rate is the most pixels the graphics card can possibly write to the local memory in one second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate also depends on many other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.