Frame Rate limit isn't capping properly

[ElementEsterine]

So since I've came back to FF14, with an upgraded PC now, I finally see a cap frame rate at 144hz. (Before I had set it at 60 fps)

If anyone hasn't guessed it by now, the problem is that it caps at 60 fps for no reason. The moment I changed from borderless windows to fullscreen, that fps cap goes from 60 to 144. And vice versa. No idea why, checked my nvidia settings for ff14. I set the preferred refresh rate to highest available, no change. So changed it back to application controlled.
Vertical sync is currently at "use the 3D application settings". I had switched that to off/on/adaptive. As always no changes to fps.
Settings is currently set at ultra with everything at max. I've lowered it to low and yet again, no changes.

The monitor I am using a BenQ XL2411Z, this monitor is 144hz monitor. I do have a second monitor which only goes up to 60hz.

Windows 10 64-bit Home
CPU: i7 4790k 4.0ghz
GPU: EVGA Geforce 1080 FTW
RAM: G.skillz 2x8gb 1866mhz
Game running DX11

As far as I am seeing there shouldn't be a bottleneck at all. No explanation on why its capping at 60 fps.
Sometimes it gets stuck at 60fps, sometimes it caps to 144fps as intended.

If there were such a bottleneck, fps should be struggling to get to 144, why would it just be stuck at 60?
Any assist would be appreciated.

[Chocolys]

When running "Borderless Window" mode, the game will be sync to your Windows 10 Desktop settings, because the game is still running in a Window even if it occupies the fullscreen with an invisible frame. Basically the display will be managed by Desktop Window Manager
Since one of your monitor is set at 60hz, Desktop Window Manager is vsync at 60hz. When you set in Final Fantasy XIV settings: 144 fps (refresh rate 1/1), because of the Desktop Window Manager it will be in fact Refresh Rate 1/1 = 60.

What you might try is set "Frame Rate Limit" to none. Since when in "Borderless Window" mode, Triple Buffering is forced by Desktop Window Manager, you should not experience visual tearing issue.

[ElementEsterine]

When running "Borderless Window" mode, the game will be sync to your Windows 10 Desktop settings, because the game is still running in a Window even if it occupies the fullscreen with an invisible frame. Basically the display will be managed by Desktop Window Manager
Since one of your monitor is set at 60hz, Desktop Window Manager is vsync at 60hz. When you set in Final Fantasy XIV settings: 144 fps (refresh rate 1/1), because of the Desktop Window Manager it will be in fact Refresh Rate 1/1 = 60.

What you might try is set "Frame Rate Limit" to none. Since when in "Borderless Window" mode, Triple Buffering is forced by Desktop Window Manager, you should not experience visual tearing issue.

Appreciate the reply and assistance! Yes, if I set frame rate limit to none, it will not limit it at 60. But it goes way over 144fps and generates needless heat.
Guess its time to look for another 144hz monitor.

I'll see if there's some workaround to this.

[Chocolys]

Alternatively It's possible to limit the frame rate directy with the nvidia driver and even per application. You might try "nvidia frame rate limiter" in a search engine, you should find easily guides about how to do that (Using Nvidia Inspector is usually the most direct way to do so)