After SU7 my fps dropped by 50% all across the board. I had it set for 30 fps, and I ended up with 15. Every time I started the sim, it started at 30 while the first animated credits are running, and then when the Pilatus Porter graphic is up, it dropped to 15 and stayed there throughout, no matter what or where I was flying at the moment. And with either DC11 or DC12, it still stayed at 15.
After a lot of head scratching, I discovered that I could get 30fps - by setting the graphics to 60fps! So that is where things stand now - locked on 60fps to get 30. No other ideas came out of a 1.5 hour session with support at the computer maker! Serious problem here…
Oh, and DX12 screws up the add-on planes too - crashes to desktop. As we say in the old country - ‘tanks fer nootin’!