9 months ago - AndrewT - Direct link
Please do a full **clean** re-install:

- move any valued save games elsewhere
- "uninstall" in Steam-EU4
- manually delete both the Steam/SteamApps/common/Europa Universalis IV AND Documents/Paradox Interactive/Europa Universalis IV folders - In particular make sure there are no files or folders left under either the Steam EU4 or Documents EU4 locations, before installing again.
- re-install game in Steam, run a Steam Verify when done.
- add EU4.exe to the exceptions list of your antivirus app; ESPECIALLY if you have Windows Defender, add it to the Ransomware "Apps Allowed Through" list.

THEN Right click on eu4.exe , properties, compatibility. Tick "disable fullScreen optimisations" untick every other box in that dialog, Apply and exit.

Edit settings.txt to say:

refreshRate=60
fullScreen=yes
borderless=no

vsync=no

Then in the launcher Game Settings menu, select fullScreen display mode.

IF that doesn'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/Europa Universalis IV/settings.txt and pdx_settings.txt .
From your Documents/Paradox Interactive/Europa Universalis IV/logs/ folder, attach here system.log , error.log , exceptions.log  
9 months ago - AndrewT - Direct link
What fps are you seeing in the game now? It should not get over 60.

Please:

- expand your Windows paging file maximum size to 32gb

Optional: Increasing the paging file size on Windows computers

On computers that have 8 GB of RAM, the suggested paging file size is 16 GB. www.ibm.com - exit every other app you can before starting the game.

Good luck with that!