How do u check fps ?
I have low rig playing low spec and it "feels" to me like 50 fps but I cant tell for sure

There's a frame limit slider somewhere in options, perhaps Video, Gameplay or HUD. I think options are unlimited, 30 or 60. He uses a 3rd party application called FRAPS.

You can pick a hotkey to move it around in all 4 corners and when it has hit the last it will hide the number in case you find it distracting after you have checked it without killing the application.

NOTE: Just make sure to change hotkeys for recording movies to something like ctrl+shift+alt+[hotkey] so you don't accidentally turn it on, it will lower performance considerably.

Take a look at the graphic options. I believe it is right above the resolution option but there is a slider for "maximum frames per second" If that is set to 30 then that would be your issue.

thanks evryone, but I tried the slider before and made no change, still getting 30 fps, regardless of the option selected (unlimited, 30, 60), on low and ultra, always 30, when I move it goes up a little bit, 35, even 40, but if i stop it goes back to 30

I re-download the installer, update and dlcs, directly from gog webpage, unistalled the game, cleaned registry and game folder, reinstalled the game, opened gog galaxy for the last update and the game now runs without the cap.

Seems like this can help with a lot of issues in the game so I recommend this first in case any issue.