about 1 year ago - AndrewT - Direct link
Right click on ck3.exe , properties, compatibility. Tick "disable fullScreen optimisations" untick every other box in that dialog, Apply and exit.
Then in the launcher Game Settings menu, select fullScreen display mode, Vsync off, cap refresh rate at 60.


If those don't help:
DXDIAG is a program you run from the Windows search box on the task bar. After running it will open a window and start collecting info with a progress bar in the lower-left corner. When it completes click the 'save all information' button and save it to a file then attach that file here.

Please attach here your Documents/Paradox Interactive/CK3/pdx_settings.txt .
From your Documents/Paradox Interactive/CK3/logs/ folder, attach here system.log , error.log , exceptions.log


AND please report the temperatures of your CPU and video (GPU)
1/ before starting the game up and
2/ after say 30 minutes' play.
If your PC's vendor has given you no way of reading temperatures, install
SPEEDFAN http://www.almico.com/sfdownload.php