CR33, you and i have the Exact same setup.
I have my “All core” at 5.1 GHz as well with Single core up to 5.3 GHz.
For the most part…FPS are fine all the time with me setting 33% VSync which nets me 40 FPS.
I have just notice with busy airports and FSLTL i get down to 30 FPS and below.
Hopefully we will hear from someone that has upgraded to the 13900k and can give real world experience.
If 14th Gen Intel changes sockets…i will either just jump into the 13900k and be done or Possibly consider the new AMD 7900X3D
Overall i am very happy with the system/setup…just like to max out settings of possible 