With G-SYNC enabled, the
“Vertical sync” option in the control panel no longer acts as V-SYNC, and actually dictates whether, one, the G-SYNC module compensates for frametime variances output by the system (which prevents tearing at all times. G-SYNC + V-SYNC
“Off” disables this behavior; see
G-SYNC 101: Range), and two, whether G-SYNC falls back on fixed refresh rate V-SYNC behavior; if V-SYNC is “
On,” G-SYNC will revert to V-SYNC behavior above its range, if V-SYNC is
“Off,” G-SYNC will disable above its range, and tearing will begin display wide.