OK, I'm using Ubuntu Gnome 15.04 wit gnome shell 3.16.1 and nvidia control panel 349.16 (think that's the newest one, correct me if i'm wrong)
I have no idea why it says 60hz under the name of my monitor when it should say 144hz.
Also in windows 8.1 when I move my cursor in circles it looks like there's more frames per second. That might be placebo tough.
So if anyone were as kind to answer/propose a solution about this, it would be very kind.