Compare any two graphics cards:
Radeon HD 5770 vs Radeon HD 6770 1GB
IntroThe Radeon HD 5770 comes with a core clock speed of 850 MHz and a GDDR5 memory frequency of 1200 MHz. It also makes use of a 128-bit memory bus, and makes use of a 40 nm design. It is comprised of 800(160x5) SPUs, 40 Texture Address Units, and 16 Raster Operation Units.
Compare all that to the Radeon HD 6770 1GB, which makes use of a 40 nm design. AMD has set the core frequency at 900 MHz. The GDDR5 memory runs at a speed of 1050 MHz on this model. It features 800 SPUs as well as 40 TAUs and 16 ROPs.
Power Usage and Theoretical BenchmarksBoth cards have the same power consumption.
In theory, the Radeon HD 5770 is 14% faster than the Radeon HD 6770 1GB overall, because of its higher bandwidth. (explain)
Texel RateThe Radeon HD 6770 1GB is a small bit (more or less 6%) better at AF than the Radeon HD 5770. (explain)
Pixel RateThe Radeon HD 6770 1GB will be a bit (more or less 6%) faster with regards to anti-aliasing than the Radeon HD 5770, and should be capable of handling higher screen 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: Memory bandwidth is the max amount of data (measured in MB per second) that can be transported past the external memory interface in a second. The number is worked out by multiplying the card's bus width by the speed of its memory. In the case of DDR type memory, it should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the better the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed in one second. This is calculated by multiplying the total texture units by the core speed of the chip. The better this number, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in a second.
Pixel Rate: Pixel rate is the most pixels that the graphics card could possibly record to its local memory in a second - measured in millions of pixels per second. The number 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 filling the screen with pixels (the image). The actual pixel rate also depends on many other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.