Hello guys! i just wanted to report back what i think it was the solution of my initial problem posted some weeks ago. After checking the connections, i realized i had the GPU connected via HMDI to my Monitor. I then changed my cable to a display port cable, connected this in the diplay port of the GPU and then to the monitor. Surprise! the FPS counter went up
If i recreate the initial set up i had (pmdg on runway at KJFK), i get well above the 30 FPS that I was seeing. I must say the performace and smoothiness was never an issue. But i just could not understand why i was stucked on 30 FPS even by not having any locked refresh rate and although i lower the graphic settings in the sim from Ultra to Low the 30 FPS were still there.
Well i can say I am not an expert in connecting stuff 
but wow! i never though that a cable connection would play such a big role in the display of FPS (not performace).
I want to thank everyone who contributed by giving ideas and taking the time to troubleshoot the issue! 