Question 60hz on 75Hz monitor

[diel.deweerdt4]

So when i'm on the interwebs, desktop or anything else that's not in fullscreen i have 75Hz. But my games can't go to 75Hz unless i put in Borderless windowed. I used to get 75Hz in fullscreen applications but it has somehow glitched so now i can only reach 60Hz in fullscreen. How do i fix this?

 

[rgd1101]

system spec? exact model of the monitor?
what connection are you using to connect gpu to monitor ?