Compare any two graphics cards:
Radeon HD 6770 1GB vs Radeon HD 6870
IntroThe Radeon HD 6770 1GB comes with a GPU core speed of 900 MHz, and the 1024 MB of GDDR5 memory runs at 1050 MHz through a 128-bit bus. It also features 800 Stream Processors, 40 Texture Address Units, and 16 ROPs.
Compare those specifications to the Radeon HD 6870, which makes use of a 40 nm design. AMD has clocked the core speed at 900 MHz. The GDDR5 memory works at a speed of 1050 MHz on this specific model. It features 1120 SPUs as well as 56 TAUs and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 6870 should be 100% faster than the Radeon HD 6770 1GB in general, due to its higher data rate. (explain)
Texel RateThe Radeon HD 6870 will be quite a bit (about 40%) more effective at AF than the Radeon HD 6770 1GB. (explain)
Pixel RateThe Radeon HD 6870 will be much (approximately 100%) more effective at full screen anti-aliasing than the Radeon HD 6770 1GB, and should be able to handle higher screen resolutions better. (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 largest amount of data (in units of MB per second) that can be transferred past the external memory interface within a second. The number is calculated by multiplying the bus width by the speed of its memory. In the case of DDR memory, it should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the bandwidth is, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are applied per second. This is worked out by multiplying the total number of texture units of the card 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 number of pixels the graphics card could possibly write 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 card's clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill 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.