16.12.2, much like 16.12.1, locks my monitor to 60hz and does not allow it to run at other refresh rates. Rolling back to 16.11.5 and earlier fixes it.
See here: https://streamable.com/1hvq
This issue persists after reboot and some intensive troubleshooting. Conclusion: driver bug.
Was reported during last driver in multiple places but you do not list it as a known issue. Sad.
Please put this into known issues and resolve it.
My GPU is a R9 Fury X and my monitor is a BenQ xl2735