Compare any two graphics cards:
Radeon HD 6770 vs Radeon HD 6870
IntroThe Radeon HD 6770 uses a 40 nm design. AMD has set the core frequency at 900 MHz. The GDDR5 RAM works at a frequency of 1050 MHz on this card. It features 800 SPUs along with 40 Texture Address Units and 16 ROPs.
Compare those specifications to the Radeon HD 6870, which comes with a clock frequency of 900 MHz and a GDDR5 memory speed of 1050 MHz. It also makes use of a 256-bit bus, and uses a 40 nm design. It is comprised of 1120 SPUs, 56 Texture Address Units, and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 6870 should in theory perform a lot faster than the Radeon HD 6770 overall. (explain)
Texel RateThe Radeon HD 6870 is quite a bit (about 40%) better at texture filtering than the Radeon HD 6770. (explain)
Pixel RateIf using a high screen resolution is important to you, then the Radeon HD 6870 is superior to the Radeon HD 6770, and very much so. (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 (in units of megabytes per second) that can be transported past the external memory interface in one second. It is calculated by multiplying the interface width by the speed of its memory. In the case of DDR type RAM, the result should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the memory bandwidth, the better the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed in one second. This number is calculated by multiplying the total number of texture units of the card by the core 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 per second.
Pixel Rate: Pixel rate is the maximum amount of pixels the video card could possibly record to the local memory per second - measured in millions of pixels per second. The number is calculated by multiplying the amount of Render Output Units by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate also depends on lots of other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.