Compare any two graphics cards:
Radeon HD 5770 vs Radeon HD 5870
IntroThe Radeon HD 5770 features a GPU core speed of 850 MHz, and the 1024 MB of GDDR5 RAM is set to run at 1200 MHz through a 128-bit bus. It also features 800(160x5) Stream Processors, 40 TAUs, and 16 Raster Operation Units.
Compare those specs to the Radeon HD 5870, which has GPU clock speed of 850 MHz, and 1024 MB of GDDR5 RAM set to run at 1200 MHz through a 256-bit bus. It also features 1600(320x5) SPUs, 80 Texture Address Units, and 32 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 5870 will be 100% faster than the Radeon HD 5770 in general, due to its greater data rate. (explain)
Texel RateThe Radeon HD 5870 is a lot (more or less 100%) faster with regards to anisotropic filtering than the Radeon HD 5770. (explain)
Pixel RateIf running with high levels of AA is important to you, then the Radeon HD 5870 is a better choice, 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 max amount of information (counted in megabytes per second) that can be moved over the external memory interface in one second. It is worked out by multiplying the bus width by its memory speed. In the case of DDR type RAM, it should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the faster 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 can be applied in one second. This figure is calculated by multiplying the total 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 in a second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics card could possibly record to its local memory in one second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of colour ROPs by the the card's 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 output rate also depends on many other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the maximum fill rate.