Thank you for the information Jibs.

I have a few additional questions regarding your issue:

When you say it doesn't obey the frame limiter, do you mean that you are getting variable frame rates when while G-sync is active? Can you lock the frame rate using another program? Does this have a different result?

You mentioned you used OBS to stream. Is this open or in the background at all times, even when you are not using it?

According to your System Report, you are using three different monitors. Do these all have G-sync? Can you disable two of them and see if this changes the issue?

You may have already tried this, but I want to mention it just in case: Try a clean boot. Simply open the task manager and select the 'Start up' tab. Disable everything here and restart the PC. Make sure to not open any other programs or overlays while playing.

We hope we can be of assistance in helping you enjoy the exciting world of Final Fantasy XIV!