kartik_9 :
Just 1080p 60 refresh rate.and want higher fps
You won't gain much of anything besides stuttering and screen tearing with that monitor. If the monitor's max is 60, then that's the most you're gonna see, even if the monitoring software you're using says otherwise. That 70/80 fps you saw was superficial - your monitor can't exceed that.
I think I saw somewhere that GTA 5 can use more than 8 gigs of ram, so if there's ANYTHING actually worth upgrading in your setup, its that.