Thanks for you comment/advice.
As said i already found some new drivers from the computer developers site which are for win10 and dating this year (at least better the win7/8 i used this far) and downgrading the nvidia again sould be no problem either. Happend already many times using MSFS i had to do this.
But as said maybe I’ll manage to do this today else tomorrow (depends on how long i still need to be working away from home)
I’ve seen the tool about the cache cleaning on flightsim.to and might give it a try too.