GTA IV vsync

[rGhost]

Guys, I have that very annoying flickering on my screen when I'm playing games full screen but especially GTA IV in which the flickering is most visible. I don't have any vsync feature in settings and I can't open Catalyst Control Center for one reason or other (my GPU is Sapphire R9 270) so what's to do ? 

[simtransporter]

Try navigating to C:\Program Files (x86)\ATI Technologies\ATI.ACE\Core-Static   

then click on CCC.

[rGhost]

No succes, the app just won't open. I was wondering why my gta doesn't have vsync settings çause I've looked on the internet and many people have this feature.