What Is V-Sync? Screen Tearing, G-Sync, FreeSync and VRR Explained
What V-Sync does, why screen tearing happens, and how G-Sync, FreeSync and VRR on TVs fix it with less input delay. Which sync setting to pick for your screen.
A horizontal seam slices across the picture during a quick turn, and for a split second the top half of the image no longer lines up with the bottom. That is screen tearing. V-Sync, short for vertical synchronisation, is the oldest fix for it: the graphics card holds each finished frame back until the display is ready to start a fresh refresh. Newer variable refresh technologies solve the same problem from the other side, by letting the display wait for the graphics card instead.
Why tearing happens at all
A monitor or TV redraws its picture at a fixed rhythm, for example 60 or 144 times per second, and it does so line by line from top to bottom. The graphics card, meanwhile, finishes frames whenever it can, and that pace changes constantly with what is happening in the game. If a new frame arrives while the screen is halfway through drawing the previous one, the lower part of that refresh shows the new image and the upper part shows the old one. Fast sideways motion makes the mismatch obvious.
Tearing can show up at any frame rate, but it is especially common when a game runs well above the display's refresh rate, a situation our guide to frames per second in games covers in more detail.
How V-Sync fixes it, and what it costs
With V-Sync on, the graphics card only swaps in a new frame during the short pause between two refreshes. Every refresh therefore shows one complete image, and the seam disappears. That tidiness comes at a price:
- Added input delay. Finished frames wait in a queue for their turn, so what you see is slightly older than it would otherwise be. In slower games nobody notices; in fast shooters many players do.
- Stutter when the frame rate dips. With classic double buffering, a game that cannot quite reach 60 on a 60 Hz screen may fall back to showing each frame for two refreshes, which feels like an abrupt drop to 30.
- Uneven pacing. Triple buffering softens those drops by keeping an extra frame ready, at the cost of a little more memory and, in some implementations, more delay.
Adaptive sync: let the screen wait instead
Variable refresh rate, usually shortened to VRR, flips the arrangement. The display starts each refresh the moment a new frame arrives, within a supported range. No tearing, no queue of waiting frames, and no sudden halving when the frame rate wobbles. Several names describe versions of the same idea:
| Name | Where you see it | Notes |
|---|---|---|
| G-Sync | Monitors paired with Nvidia graphics cards | Comes in tiers; many monitors are certified as compatible rather than using a dedicated module |
| FreeSync | Monitors and TVs paired with AMD graphics and some consoles | Built on the open Adaptive-Sync standard; higher tiers add more features |
| VESA Adaptive-Sync | DisplayPort monitors | The underlying open standard that many monitors support |
| HDMI VRR | TVs with HDMI 2.1 features, current consoles and PCs | Often only available on certain HDMI ports of a TV |
Every VRR display has a working range, such as 48 Hz up to its maximum refresh rate. Inside it, motion stays smooth. Below it, some displays use low framerate compensation, showing each frame twice so the panel stays within its range. That makes the range worth checking when comparing screens.
VRR and ALLM on a television
Living-room setups have their own pair of acronyms. VRR works as described above once both the TV and the console or PC have it switched on, and usually only through the HDMI input marked for gaming features. ALLM, short for Auto Low Latency Mode, is a separate HDMI feature that lets the console tell the TV to switch into its game mode automatically, turning off picture processing that would otherwise add delay. If a TV feels sluggish with a console, those two settings and the choice of HDMI port are the first things to check.
Which setting to use
| Your setup | A sensible choice |
|---|---|
| VRR-capable monitor or TV | Turn on VRR in both the display and the graphics or console settings, and cap the frame rate a few frames below the maximum refresh rate |
| Fixed-refresh screen, slower games | V-Sync on; the small delay is rarely noticeable and the clean image is worth it |
| Fixed-refresh screen, competitive play | V-Sync off with a frame cap, accepting occasional tearing for quicker response |
| Game with frame generation enabled | Follow the game's own guidance, since these features often expect VRR and manage sync themselves (more in our DLSS and frame generation guide) |
Mistakes that undo the fix
- Enabling VRR on the monitor but not in the graphics driver, or the other way round.
- Using an old cable or the wrong port, so the display falls back to fixed refresh.
- Leaving the desktop at 60 Hz on a high refresh-rate monitor; check the refresh setting in the operating system's display options.
- Running the frame rate far above the VRR range, which brings tearing back.
- Confusing tearing with smearing. Blurry trails behind moving objects are a pixel-speed issue instead, explained in our guide to monitor response time.
Good sync settings cost nothing and make every other upgrade feel better, from a new graphics card to the controllers in our list of favourite PC gaming gadgets.
