I installed windows 10, update to 11 on a Mac Pro 5,1 thru open core (followed instructions in sticky thread from Mac Pro forum). It works fine but it is extremely slow, even after installing all drivers from boot camp. Any clue please ? Thanks.
Do you still have windows 10 installed? Look up on youtube how to safely uninstall windows 10 and it's components correctly and not just dump it into trash while having booting up on windows 11.