Monitor signalling in/out at 120 Hz

[Angleton]

Yesterday I purchased a new monitor to replace my old Samsung syncmaster s23b300. My new monitor is a MSI optix mag27c: https://www.msi.com/Monitor/Optix-MAG27C

When I installed the monitor I set the refresh rate at 120 Hz without encountering any problem.

Today, I decided to look at KSP, with my new monitor. Unfortunately, the Monitor signalling in/out (look random). Outside the game, no problem, but when I played KSP, the in/out monitor was a recurring issue.

The monitor is able to display its refresh rate. Outside the game, it was always at 120 Hz. When I played KSP the refresh rate was constantly changing (from 59 to 83 hz). After noticing that, I changed the refresh rate of the monitor to 60 Hz and it solve the KSP problem.

I wanted to know if that situation is normal? Is it possible to play KSP at 120 Hz (or any other refresh rate)?

Thanks

Edited September 6, 2019 by Angleton
grammar