What VSync actually does

Seeing a line tear across the screen when you turn? VSync makes the graphics card hold a finished frame until the monitor starts its next refresh from the top of the screen. The name is vertical sync. NVIDIA’s Manage 3D Settings help says the application’s frame rate is synchronized with the display refresh rate to eliminate tearing. With it on, one trip shows one whole frame. With it off, a new frame can arrive halfway down, so the top is new and the bottom is old.

I play Zarya in Overwatch on a 1080p 240 Hz panel and keep a 1440p 155 Hz panel for everything that wants more pixels, driven by an RTX 5080 and an AMD Ryzen 9 9950X3D2. VSync is a wait, not a new Hertz. More guides.

Variable refresh is the other way to line a frame up with the panel: the panel moves the start of the refresh. VSync does not move the refresh. The frame waits. A cap is a third switch. It limits how many frames the card draws. VSync never chooses that number.

What to check first

VSync holds a finished frame until the monitor starts its next trip. The horizontal cut goes away. A late frame repeats for a whole trip. It does not add frames.

What you seeNot sure yetA horizontal cut while turningThe picture stays wholeThe picture sticks, then jumpsVariable refreshNot sure yetIt is offIt is onThe frame rateNot sure yetUnder the monitor's refreshOver the monitor's refresh

What this means

Read the picture

Turn the camera. A horizontal line is tearing; a stutter is a late frame. Know which one you see before you change VSync.

VSync only fixes tearing (the horizontal line), not stutter.

Off is the picture you have, including the cut. On is a rule about when that picture may change. None of the three columns adds a frame the card did not finish.

Refresh runs on a fixed clock

The panel draws in rows, from the top to the bottom, then starts again. Refresh rate is how often that trip starts when the rate is fixed. Microsoft’s Advanced display page says a 60 Hz display updates the screen 60 times per second. A 155 Hz panel, the sharper screen I actually use, can start it 155 times. A 240 Hz panel, the Overwatch screen, can start it 240 times. Neither one starts an extra trip because a game finished a frame early.

The gap is 1,000 divided by the Hertz. At 60 Hz that is about 16.7 milliseconds. At 155 Hz it is about 6.5. At 240 Hz it is about 4.2. Those are spaces on a schedule. They are not response time.

The card finishes frames on its own clock. If it swaps in a new frame while the panel is halfway down, you see the cut. It shows most when the camera turns, because the two halves disagree. VSync off allows that swap. The cable is not the fault. The frame did not wait.

Set the rate you paid for before you judge the switch. Windows shows it under Settings, System, Display, Advanced display. A 240 Hz panel left at 60 makes every wait a 60 Hz wait. VSync cannot raise it. How to set 144 Hz is the same page for any Hertz that listing pairs with the resolution you are using.

On means the frame waits

VSync on refuses the swap until the next refresh starts. The cut goes away, because the whole trip is one frame. The cost is the wait. A frame that finished just after a trip began sits until the next one. A click that landed in that frame shows up when the refresh takes it, not halfway down the screen.

NVIDIA’s system latency guide names that cost back pressure. The display tells the pipeline to slow down. The wait is not only the one trip you can see. It can pile frames in the queue behind it. That is why the same guide’s first latency tip is still “turn off VSYNC if you are willing to tolerate tearing,” and why it tells you to flip the line in the game and in the NVIDIA Control Panel.

The wait is one trip, not an open-ended pause. Miss again and the old picture holds for another gap. That second gap is the hitch. NVIDIA’s Adaptive VSync page is blunt: when VSync is on and the frame rate drops below refresh, the lock can fall to the nearest lower step, such as 45 or 30 on a 60 Hz screen. The monitor did not change its rate. On does not draw the frame that was late.

If the counter sits on that refresh and never dips, On and Off can look almost the same. Off can still cut, because a frame that finishes a little early is allowed to swap mid-trip. When the card is already ahead, On still shows one frame per trip and drops the rest. What you give up is the little delay those early frames can trim.

A cap is not this wait. A cap refuses to draw frames above a number. VSync refuses to show a finished frame until the refresh starts. You can use one without the other.

NVIDIA’s other words for the same wait

The game menu usually offers Off and On. The NVIDIA Control Panel, under Manage 3D Settings, Vertical sync, lists more. Here’s what NVIDIA’s own help says.

• Use the 3D application setting — the game decides. NVIDIA’s driver note from 461.09 says to leave the global line here. Forcing Off globally can tear even in a window, because later drivers let some apps present on their own plane.
• Off — NVIDIA’s help says this is useful if performance is more important than image quality. The cut can return.
• On — useful for eliminating tearing. The frame waits.
• Adaptive — turns VSync on only when the frame rate is faster than the refresh rate. High frames lose the cut. Low frames drop the hitch. The same help says this line appears only when Monitor Technology is ULMB or Fixed Refresh Rate.
• Adaptive (half refresh rate) — the same idea, but the on-threshold is half the Hertz. NVIDIA says that one is for extremely low frame rates.
• Fast — “improves latency without introducing tearing.” The Control Panel lists it on Pascal and later, single-GPU. NVIDIA’s Fast Sync FAQ says it is meant for games running about three times the refresh or more, and that a DirectX 12 title set to Fast falls back to Application Controlled. A second NVIDIA FAQ puts the floor at Maxwell (GeForce 900 series) and says SLI or 3D Stereo hides the option.

None of those labels is variable refresh. Adaptive still uses a fixed trip. Fast still picks a whole frame to scan. NVIDIA’s Adaptive page points at G-SYNC as the better way to drop the stutter, the tear, and the extra wait.

Triple buffering is a different Control Panel line. NVIDIA says it applies to OpenGL, and that it improves performance when Vertical sync is also on. It is not a second VSync. Leave it unless the game is OpenGL and you already want that buffer.

Where you turn it on

The switch is in the game’s graphics menu, named VSync, vertical sync, or sometimes just sync. Off and On are the two states that matter in the game. Set the monitor to the refresh rate you are actually using first. Then set one control, not two that fight.

If the game says Off and the cut is still gone, or the game says On and the cut remains, the driver’s Vertical sync line is overriding the game. Set that line to Use the 3D application setting, then use the game’s switch. One control is the wait. The other should stay out of the way.

NVIDIA’s latency guide adds two limits worth knowing. VSync On in the Control Panel only works for fullscreen applications. On an MS Hybrid laptop that On line is not supported. If you are in a borderless window and you want the G-SYNC plus VSync plus Reflex stack, use the in-game line. I play on a desktop RTX 5080.

Intel’s graphics note is the other-card version: Always On, Always Off, or Application Controlled, and only in fullscreen. The rule is still one control.

Variable refresh is the other clock

VRR lets the monitor change how often it starts a new picture, so that start can meet a frame the PC already drew. NVIDIA G-SYNC is one name for that. G-SYNC Compatible is NVIDIA’s test of a panel that already speaks the standard signal. FreeSync is AMD’s name. Microsoft’s Advanced display page will tell you whether the selected screen supports VRR.

Inside that range, the panel already starts the refresh with a whole frame. Leave VSync off in the game if the picture is already whole and you have not turned on the no-tear stack below. A cut that appears only when the counter sits on the maximum is the panel at its ceiling. On will hold the extra frame. It will not start a faster trip.

Microsoft’s DXGI page explains it for developers. Variable refresh rate displays require tearing to be enabled. That is also called VSync-off support. The present call has to be allowed to skip the fixed wait. That is why a game that forces VSync On can stop the panel from following frames even when the logo is on the box.

Then NVIDIA’s latency guide adds the user recipe on top of that. For G-SYNC gamers who do not want a tear, keeping VSync On while using NVIDIA Reflex or Ultra Low Latency Mode will automatically cap the framerate below the refresh rate, so VSync does not pile the queue back up. NVIDIA also says that stack has a little more latency than uncapped Reflex with tearing allowed. If that stack is already on, do not add a second cap above it.

If you cap by hand instead, NVIDIA’s Max Frame Rate note says to set that control slightly below the display’s maximum refresh to stay in the VRR range. Three under is the usual safety margin: 237 at 240 Hz, 152 at 155 Hz, 141 at 144. That number is a limiter overshoot cushion. It is not a VSync setting.

Windows has one more switch. Settings, System, Display, Graphics, then Variable refresh rate. Microsoft’s DirectX blog says the toggle appears only when the monitor and a WDDM 2.6 driver already support G-SYNC, FreeSync, or Adaptive-Sync, and that it adds VRR to older DirectX 11 fullscreen games that never asked for it. It does not replace the card’s control panel.

Windows 11 Dynamic Refresh Rate lives on Advanced display. Microsoft says DRR needs VRR and at least 120 Hz, and that it can limit the maximum refresh of games not designed for VRR. If a title looks stuck, turn DRR off. That toggle is not VSync.

The asterisk is not a cable

Microsoft’s Advanced display page puts an asterisk next to refresh rates that do not support the current resolution. Selecting one of those rates changes the resolution so the higher Hertz can run.

If you wanted 1440p at 155 and the star drops the picture to 1080p, that pair is not available at the current mode. Put the resolution back. The asterisk is not a cable diagnosis. A cable can still be one reason the pair is missing. So can a dock, a duplicated 60 Hz laptop panel, or a listing that only offers the high Hertz at a lower resolution.

I keep 240 Hz at 1080p and 155 Hz at 1440p. I judge the wait on those two modes.

What VSync does not change

It does not raise the frame rate or the refresh rate. A 60 Hz screen still shows 60 trips. It does not create a frame, and it does not rebuild a smaller picture into a larger one. Raising FPS is the picture-count page. It does not make the pixel faster. That is response time. It does not time the click. That is NVIDIA Reflex. It does not follow a late frame by moving the refresh. That is VRR.

If the camera turns and you never see a cut, leave it off. On is for a split you can see and would rather trade for a wait.

What I would set

• Look for the cut first. If there is none, leave VSync off.
• If the cut is there and VRR is off, On removes the split. Accept the wait.
• If VRR is on and you are using NVIDIA’s G-SYNC plus VSync plus Reflex recipe, do not add a second cap above it. Otherwise leave VSync off in the game while the counter stays in range.
• Leave the Control Panel on Use the 3D application setting unless you have a reason to force one game.
• Adaptive and Fast are not G-SYNC. Fast wants a counter about three times the Hertz, and it will not stick on DirectX 12.
• Set the Hertz on Advanced display first. A starred rate that drops the resolution is not a new cable.

On holds a finished frame for the next refresh. Off shows the picture you have, including the cut. Neither one draws a frame the 5080 did not finish. More guides.

Related: Guides, What crosshair placement is, aim tools, Hardware.

Common questions

What is VSync?

A setting that makes your graphics card wait for the monitor's next refresh before showing a new frame. It stops screen tearing.

Should I turn VSync on or off?

Off for competitive games, where lower input lag matters more. On if tearing bothers you and you don't mind a little extra delay. With G-SYNC or FreeSync, many players use VSync with an FPS cap just below the refresh rate.

Does VSync add input lag?

Yes, it can, because finished frames wait for the monitor before they're shown.

What's the difference between VSync and G-SYNC or FreeSync?

VSync makes the GPU wait for the monitor. G-SYNC and FreeSync make the monitor wait for the GPU, which removes tearing with much less lag.