And all apologies in advance but I would not expect an answer since the display (monitor, LCD, laptop?) may or may not support full range. My Lenovo y510p dithers to get some colors so it's not a question for Nvidia.
https://www.google.com/search?q=nvidia+10+bit+color broaches the question in another way. This adds to the problem that the card matters.
As I don't know the card, display or driver version all I can write is Nvidia is only one part of the display system.
I have it set to do so in my graphics card settings (NVIDIA Control Panel) but I am not sure that it ever enables... and I have read it as problems. If you don't know an answer for this do you know of a way for me to test it? (I do know that my display is capable of displaying full dynamic range, also I posted this question in the nvidia forums but they never answer me.)

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