Set what GPU should Linux app run in:
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In the command line (or in the desktop file for each app), add this before the program:

To use Intel GPU:
DRI_PRIME=0

To use NVIDIA GPU:
DRI_PRIME=1

exsample:
DRI_PRIME=0 ffmpeg


source: https://askubuntu.com/questions/596855/choose-which-gpu-to-use-for-each-application
Date: January 27th, 2022