Same time as you wrote I also figured it by just a factory reset. It wasn't the Picture Mode or something it was the Response Time setting which I set to faster.
If you don't mind I have another question then after enabling FreeSync Ultimate Engine.
In my Nvidia Control Panel I now can tick enable G-SYNC, G-SYNC Compatable.
-Curious why I can enable the same thing for my 2nd Monitor which is an older 27" Samsung Model from 2015/2016 which does not have G-Sync or Freesync.
-Specific Settings in the control panel are for G-Sync only?
-It is recommended to disable V-Sync if FreeSync is enabled right?
-Is it recommended to run FreeSync even if for example only reach 50 FPS in certain games.