144 fps VSync caps at 60 fps

This really just comes out of nowhere.

I always have my VSync setting to 144 fps since I have a 144hz monitor. I was playing tonight and everything was working fine. Then all of a sudden my game dropped and capped to 60 fps. All the other VSync settings (except for 72 fps) are working as I expect them to. Turning off Vsync works as expected too.

I have tried restarting the game, restarting my PC, checked my display adapter settings, and haven't seen anything wrong. It really just happened randomly while I was in game.

Any idea what could it be? I can play with Vsync off nbd, but I really want to know what happened to my game.

My set up just for reference:

• i5 6600K
• Asus Z170 Pro Gaming MB
• EVGA GTX 1070 FTW
• Dell S2716 GSync monitor
• 2x 8GB of Corsair 2400 ram

The whole system is sufficiently cooled and consistently stay below 60C during gameplay.