G-Sync + V-Sync + Reflex: The Lowest-Latency Setup
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The lowest-latency tear-free setup is the classic combo: variable refresh (G-Sync or FreeSync) ON, V-Sync ON in the driver (not in-game), an FPS cap a few frames below your refresh rate, and NVIDIA Reflex (or AMD Anti-Lag) ON in supported games. Done together, these give you smooth, tear-free frames with latency close to running V-Sync off — the best of both worlds.
Each piece does one job — stay inside the variable-refresh range and never touch the V-Sync ceiling.
The setup at a glance
| Setting | Value | Why |
|---|---|---|
| G-Sync / FreeSync | On (fullscreen + windowed) | Monitor refreshes in sync with your frames — no tearing |
| V-Sync (driver) | On | Safety net against tearing if FPS spikes to the ceiling |
| V-Sync (in-game) | Off | In-game V-Sync adds its own frame queue |
| FPS cap | ~3–5 below refresh | Keeps you inside the G-Sync range |
| Reflex / Anti-Lag | On | Removes render-queue latency, auto-caps below ceiling |
That is the entire recipe. The rest of this guide explains why each piece earns its place.
Why G-Sync (or FreeSync) goes on
Variable refresh syncs the monitor’s refresh to your actual frame rate instead of a fixed cadence. Inside its range, every frame is shown whole and immediately — no tearing, no waiting for a fixed refresh slot. This is the foundation; without it you are choosing between tearing (V-Sync off) and buffering lag (V-Sync on).
Why V-Sync goes ON — in the driver
This is the counterintuitive part. With G-Sync active and an FPS cap below refresh, you stay inside the variable-refresh range where V-Sync essentially never engages. But if your frame rate momentarily spikes to the top of the range, plain G-Sync alone would tear. Driver-level V-Sync acts purely as a ceiling guard: it catches those edge cases and prevents tearing without adding the constant frame-queue latency it causes when used alone. Enable it in the NVIDIA Control Panel or AMD driver, and turn the in-game V-Sync option off so the two don’t fight.
Why the FPS cap below refresh is the key
The cap is what keeps you inside the G-Sync range and away from the V-Sync ceiling, where buffering and latency would return. Set it a few frames under your refresh rate:
- 144 Hz → cap around 138
- 165 Hz → cap around 158
- 240 Hz → cap around 225
Use an in-engine cap or a reliable external limiter. For the full reasoning and how much margin to leave, see Best FPS Cap for Low Latency.
Why Reflex (or Anti-Lag) goes on
In supported games, NVIDIA Reflex does two things: it removes the render queue so the CPU stops running frames ahead of the GPU, and it dynamically caps your frame rate just below the G-Sync ceiling for you. That means in a Reflex game you can let Reflex handle the cap automatically — it does the job better than a manual limiter. AMD users get the same behavior from AMD Anti-Lag 2. If your game lacks Reflex, the manual cap above does the equivalent work.
Putting it together and verifying
Build the chain in order: variable refresh on, driver V-Sync on, in-game V-Sync off, FPS cap below refresh (or Reflex on to handle it), and a fine Windows timer resolution via Tier1Timer for steady frame pacing. Then confirm the result rather than trusting feel — measure your input lag and watch the PC Latency overlay to verify the V-Sync penalty is gone.
Related guides
- NVIDIA Reflex: Should You Turn It On?
- Best FPS Cap for Low Latency
- How to Optimize Your Monitor for Gaming + Reduce Input Delay
- How to Minimize Input Delay for Competitive Gaming
- How to Measure Input Lag
The magic of this setup is that every piece has one job: G-Sync removes tearing, the FPS cap keeps you in its range, driver V-Sync guards the ceiling, and Reflex strips the render queue. Configure all four and you get tear-free smoothness with latency that feels almost identical to running V-Sync off — which is exactly why this combo has been the competitive standard for years.
Frequently asked questions
Why turn V-Sync ON with G-Sync if V-Sync adds lag?
Inside the G-Sync range, V-Sync barely engages — the monitor refreshes in sync with your frames, so there is nothing to buffer. Control-panel V-Sync acts as a safety net that prevents tearing if your frame rate briefly spikes to the top of the range. With an FPS cap below refresh, you almost never hit the V-Sync ceiling, so you get tear-free frames without the classic V-Sync latency penalty.
Should I cap FPS below my refresh rate with G-Sync?
Yes. Capping a few frames below your refresh rate (for example 138 on a 144 Hz panel, or 225 on 240 Hz) keeps you inside the G-Sync range and stops you from ever hitting the V-Sync ceiling where buffering and latency would creep in. This cap is the single most important part of the low-latency variable-refresh setup.
Where do I enable V-Sync — in the game or the control panel?
In the NVIDIA Control Panel (or AMD's driver), not in the game. Driver-level V-Sync interacts correctly with G-Sync/FreeSync, while in-game V-Sync can add its own frame queue and conflict with the variable-refresh logic. Set V-Sync to On globally in the driver and leave the in-game V-Sync option off.
Does NVIDIA Reflex replace the FPS cap?
It largely does in supported games. Reflex dynamically caps your frame rate just below the G-Sync ceiling and removes render-queue latency, so it does the job of a manual cap automatically and better. If your game has Reflex, turn it on and you can skip the manual cap; if it doesn't, set a manual cap a few frames below refresh.
Does this setup work with AMD FreeSync and Anti-Lag?
Yes, the same principles apply. Enable FreeSync, turn on V-Sync in AMD's driver, cap FPS below refresh, and use AMD Anti-Lag 2 (or Anti-Lag in supported titles) as the Reflex equivalent. The mechanism is identical: stay inside the variable-refresh range and avoid the V-Sync ceiling.