Ok I have new information...
So a new nvidia update came out today 12/20..I installed it and it reverted the Physx setting back to auto. This means whenever you update nvidia you have to check to see that it keeps it set to your nvidia card

Quote Originally Posted by MatthiasS View Post
Never had a slowdown issue on my GTX 1070.
I think the problem is related to cpu, if your cpu is too good it will try to use that instead of your nvidia card..