Forgot to mention resolution. It's at 2560x1080 which I can contribute some of my low FPS to but I don't bother with 4k.
Though even with SL in windowed mode filling half my screen it's laggy.
I'm mostly testing it out at a rather laggy sim but then comparing what I'm getting FPS wise to folks with also looking the same direction with similar settings etc. They'll be 20-30 while I'm 10-15.
Using HWMonitor yeah CPU's not really going over 25% most the time. Maxed at 40% when I was intentionally trying to be crazy with my camera.
The GPU though fluctuates nonstop from 0-100% hitting numbers inbetween but still jumping to 100 repeatedly. (SL in windowed mode half the screen). Cards also pretty much new as well as PSU.
I'll look into getting windows 10, was only holding off because of some older software in the past but they should be fine now.
Appreciate the response, even if you're as confused as I am haha.