I am viewing on a 30-bit capable, Asus PA249Q monitor, connected to a 30-bit capable Quadro K620 card via DisplayPort, in Win 8.1 Pro Bios and graphics card have the last driver I have installed Photoshop CC 2014.2 and enable acceleration, open GL and the 30 bit monitor option in preference menu.
10 bit Color Depth Demo Application by NEC work fine and tell me that the 30 bit in my system is activate! To test if the 10 bit color depth mode is working I open the file testramp.psd that is a gray scale gradient into Photoshop. If the 10 bit color depth mode is working properly, the gradient appears smooth. In case of 8 bit color depth you will see banding.
unfortunately, I see banding but my system is 30-bit capable!
The same situation with an ATI FirePRO V5800
Why photoshop doesn't support 30 bit monitor? is this a bug?