You can configure GSYNC to be OFF for some games and ON for others.
Some games really look good with GSYNC on the Cosair Xeneon Flex -- like System Shock. You simply have to make sure you keep framerates 100fps or above to prevent the flickering. The experience with GSYNC is much better ON than OFF for certain types of games, in my experience, since jitter (from non-VRR) can be more annoying to me. The way GSYNC fixes jittering more than exceeds the flicker disadvantage, as long as the game is very VRR
One problem when capping lower frame rates (e.g. 60fps) is the rapid entry/exit of LFC can be individual flicker events. LFC typically occurs at ~48Hz, but sometimes triggers on/off even if you're doing 60fps. In this situation, making sure the framerate never falls below 60fps, is key.
One method is to use GSYNC for fullscreen exclusive games only, and configure it on a per-game basis (global GSYNC turned off, but GSYNC turned on a per-game basis). There's way to use NVCP to use a whitelisting approach, where GSYNC is only enabled only when you run certain games.
The NVCP "whitelist approach" for GSYNC where it's off by default except for certain games:
- Monitor -> Adaptive Sync -> ON
- NVCP -> Set up G-SYNC -> ON only for fullscreen
- NVCP -> Manage 3D Settings -> Global Settings -> Monitor Technology -> Fixed Refresh
- NVCP -> Manage 3D Settings -> Program Settings -> Choose game to whitelist -> Monitor Technology -> G-SYNC
- NVCP -> Manage 3D Settings -> Program Settings -> Choose game to whitelist -> Vertical Sync -> ON
- NVCP -> Manage 3D Settings -> Program Settings -> Choose game to whitelist -> Max Frame Rate -> 235 (or use RTSS)
- Game Settings -> VSYNC -> OFF
NVCP per-game setting - GSYNC ON only for most co-operative games.
In this situation, G-SYNC is always disabled except for specific games. You can use VSYNC OFF for things like CS:GO/Overwatch, but G-SYNC for games like System Shock that performs better with OLED VRR ON.
Also, OLED VRR flicker is from the framerate yo-yo effect -- sudden halvings or triplings of frame rates. Like when bringing up menu or when a game is loading/shader compiling/texturestreaming. This is one of the main causes of VRR flicker problems on any LCD/OLED that is subject to VRR flicker (even some of my LCDs have a slight VRR flicker effect during large framerate yoyo effects). Another reasion is rapid exit/entry of LFC mode (where drivers' framerate suddenly doubles to prevent refresh cycles from falling below min VRR Hz range). So even if you have 60fps, you're already dangerously close single frames being 48fps, it may mean some frametimes are 1/40sec and other frametimes 1/80sec, to average 1/60sec. A single frametime into LFC territory, thus, can be a minor flicker event, especially if you love doing "RTX ON" and Ultra settings, which can often cause a single-frametime dip into LFC territory -- one too-slow refresh cycle will often create flicker event as it suddenly transitions into LFC vs non-LFC mode. Also, many graphics drivers will pre-emptively enter LFC mode a bit 'early' (this is annoying). Some people resort to range-editing the VRR range in ToastyX CRU to mitigate this, but this does not always work for all games.
The key to avoiding flicker events is avoiding too-slow frametimes (making sure no frametimes spike above ~10ms), which means you have to fiddle with the game settings to keep frame rates in the triple digits.