Solved Unusual graphics problem!

My screen supports 10-bit HDR, so I set the Nvidia driver to output 10-bit and enabled HDR in Windows. The Advanced display settings show as '10-bit' (the screen is actually 8-bit+FRC) but 10-bit output support is there.

New graphics driver today, booted in Safe mode, did the DDR, installed new drivers. The same process I've always done with new GPU drivers.
Restarted - no 10-bit support in the Nvidia driver, although HDR is available in Windows. The Advanced display now shows '8-bit plus dithering'

So, thinking it's the new drivers, I restored a system image I made this morning. Same problem, no 10-bit working.
Uninstalled the new AMD chipset driver, same problem.

I don't get what's happened here, if the driver was bad then the known-working backup should still work?

So I tried a clean install on a different drive, same hardware. 10-bit? All working. Updated chipset and Nvidia drivers, still working. Exactly the same Windows build, drivers and hardware (22621.105)

Clearly NOT a hardware problem but what could have happened here? Something must have changed before the daily image backup yesterday morning that I'm not aware of but I'm at a loss why I've suddenly lost 10-bit graphics support

If your display is 8 bit + 2 bits FRC (frame rate control, temporal dithering), then it is, in fact, 8 bits plus dithering. (Nothing wrong with that; most still call that a 10 bit display.)

I'm surprised. In the past, I used 8+2 monitors, and the nVidia drivers showed 10 bits. (They were not HDR capable monitors, though.) MY current monitors support HDR, but they are native 10 bit, so I can't check what the nVidia control panel would say with FRC.

bobkn said:

If your display is 8 bit + 2 bits FRC (frame rate control, temporal dithering), then it is, in fact, 8 bits plus dithering. (Nothing wrong with that; most still call that a 10 bit display.)

I'm surprised. In the past, I used 8+2 monitors, and the nVidia drivers showed 10 bits. (They were not HDR capable monitors, though.) MY current monitors support HDR, but they are native 10 bit, so I can't check what the nVidia control panel would say with FRC.

Click to expand...

Mine has ALWAYS said 10-bit though, now it's only saying 8-bit,and the fact that a clean install on the same hardware shows as 10-bit is very strange. I can tell that the display isn't right in 8-bit mode

Anyway I took the nuclear option, did a clean install of Windows 11 this morning. 10-bit video output is working properly now, and I now have Smart App control in Device Security.

BrianInEngland said:

Mine has ALWAYS said 10-bit though, now it's only saying 8-bit,and the fact that a clean install on the same hardware shows as 10-bit is very strange. I can tell that the display isn't right in 8-bit mode

Anyway I took the nuclear option, did a clean install of Windows 11 this morning. 10-bit video output is working properly now, and I now have Smart App control in Device Security.

Click to expand...

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