Compare any two graphics cards:
Radeon HD 5770 vs Radeon HD 5870
IntroThe Radeon HD 5770 makes use of a 40 nm design. AMD has clocked the core frequency at 850 MHz. The GDDR5 memory runs at a frequency of 1200 MHz on this card. It features 800(160x5) SPUs as well as 40 Texture Address Units and 16 Rasterization Operator Units.
Compare all of that to the Radeon HD 5870, which has a GPU core clock speed of 850 MHz, and 1024 MB of GDDR5 RAM running at 1200 MHz through a 256-bit bus. It also is made up of 1600(320x5) Stream Processors, 80 Texture Address Units, and 32 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 5870 should be 100% faster than the Radeon HD 5770 in general, because of its greater data rate. (explain)
Texel RateThe Radeon HD 5870 should be quite a bit (approximately 100%) more effective at anisotropic filtering than the Radeon HD 5770. (explain)
Pixel RateThe Radeon HD 5870 is much (approximately 100%) faster with regards to AA than the Radeon HD 5770, and able to handle higher resolutions while still performing well. (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 maximum amount of data (measured in megabytes per second) that can be transferred across the external memory interface in a second. It's worked out by multiplying the card's bus width by its memory clock speed. If the card has DDR type memory, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed per second. This number is worked out by multiplying the total number of texture units by the core clock 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 the graphics card could possibly record to the local memory in a second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate is also dependant on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.