Today's VSync for computers sucks. I have Radeon HD 5750 of 2014; when I enable VSync in a film, a Mortal Kombat, it reduces FPS in twice when an actor is moving half-horizontally.
1920x1080 with VSync [ON] gives huge load on a CPU (about 87%) and my system gets to work on edge.
...2 gigs of RAM, AMD Athlon II X2 on 2.9 GHz and a modern graphics - rediculous!
P.S. drivers seem to not do so far too much with it.