Compare any two graphics cards:
Radeon HD 5870 vs Radeon R9 270X
IntroThe Radeon HD 5870 comes with a GPU clock speed of 850 MHz, and the 1024 MB of GDDR5 RAM runs at 1200 MHz through a 256-bit bus. It also is made up of 1600(320x5) SPUs, 80 TAUs, and 32 Raster Operation Units.
Compare that to the Radeon R9 270X, which has core speeds of 1000 MHz on the GPU, and 1400 MHz on the 2048 MB of GDDR5 RAM. It features 1280 SPUs as well as 80 TAUs and 32 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon R9 270X should be a little bit faster than the Radeon HD 5870 overall. (explain)
Texel RateThe Radeon R9 270X is just a bit (more or less 18%) better at AF than the Radeon HD 5870. (explain)
Pixel RateIf running with lots of anti-aliasing 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 largest amount of data (counted in megabytes per second) that can be moved over the external memory interface within a second. The number is worked out by multiplying the bus width by its memory clock speed. If the card has DDR RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are processed per second. This figure is worked out by multiplying the total amount of texture units by the core clock speed of the chip. The higher the texel rate, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.
Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card could possibly write to its local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the number of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate is also dependant on quite a few other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the max fill rate.