Has this always happened ever since you've had this game? Or only since when?
When you say your screen goes black, do you mean the monitor turns off? Or the computer hangs or powers off? Or what exactly? What do you have to do to recover?
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
Please report the temperatures of your CPU and video (GPU)
1/ before starting the game up and
2/ after say 10 minutes' play.
If your PC's vendor has given you no way of reading temperatures, install
SP...
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