In gaming mode on the Steam Deck the CPU is presented to the games as having 8 cores instead of 4 cores with 8 threads. This seems to increase performance for some titles. If you want to use this in desktop mode or on your desktop PC you can achieve the same results with the environment variable WINE_CPU_TOPOLOGY. Gaming mode on the Deck uses WINE_CPU_TOPOLOGY=8:0,1,2,3,4,5,6,7. You can see everything else they do in /usr/bin/gamescope-session. I leave how to set the variable in the Wine frontend of your choice as an exercise for the reader.