I recommend trying the GP4 installation available at GP4 Central (sorry mortal if that is pedaling warez, i will remove the comment if it's not OK). It is pre-patched and ready to go, and stable as GP4 can be... Be aware that GP4 has always been, and always will be, a temperamental SOB of a game. Sometimes it will just crash, no reason necessary.
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Intel NUC 8i3, 8GB RAM, MS Sidewinder Wheel