Spatial/temporal dithering provides 30-bit color quality on 24-bit and 18-bit displays
http://ati.amd.com/products/Radeonhd4800/specs.html
To avoid confusion, bit depth is per RGB in the subject, while in advertisement its put together. 30-bit = 10-bit Red, 10-bit Blue and 10-bit Green.
To show how many colors we are talking about (and why its worthy to make a thread upon):
6-bit:
64x64x64= 262 144 colors
8-bit:
256x256x256 = 16 777 216 colors
10-bit:
1024x1024x1024 = 1 073 741 824 colors
Spatial/temporal dithering are methods to simulate more colors then what the screen have physically. You can see it in all the TN based screens of today, where they use dithering to get "8-bit".
To get higher bit depth then 8-bit, you need Vista or another OS that supports higher then 8-bit.
This is bigger then getting some extra AA, especially if to have Blueray on the computer.
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I've posted a bit around trying to figure out how well this is implemented, but it doesn't seem like its supported yet in the drivers. Have anyone sucessfully seen this in action?
They are also supposed to support colorspace conversion and more. Neither of this I've seen any evidence of support in on any reviews or any forum. Does anyone have a clue?