G-SYNC 101: Control Panel


G-SYNC Module

The G-SYNC module is a small chip that replaces the display’s standard internal scaler, and contains enough onboard memory to hold and process a single frame at a time.

The module exploits the vertical blanking interval (the span between the previous and next frame scan) to manipulate the display’s internal timings; performing G2G (gray to gray) overdrive calculations to prevent ghosting, and synchronizing the display’s refresh rate to the GPU’s render rate to eliminate tearing, along with the delayed frame delivery and adjoining stutter caused by traditional syncing methods.

G-SYNC Demo

The below Blur Busters Test UFO motion test pattern uses motion interpolation techniques to simulate the seamless framerate transitions G-SYNC provides within the refresh rate, when directly compared to standalone V-SYNC.

G-SYNC Activation

“Enable for full screen mode” (exclusive fullscreen functionality only) will automatically engage when a supported display is connected to the GPU. If G-SYNC behavior is suspect or non-functioning, untick the “Enable G-SYNC, G-SYNC Compatible” box, apply, re-tick, and apply.

Blur Buster's G-SYNC 101: Control Panel

G-SYNC Windowed Mode

“Enable for windowed and full screen mode” allows G-SYNC support for windowed and borderless windowed mode. This option was introduced in a 2015 driver update, and by manipulating the DWM (Desktop Windows Manager) framebuffer, enables G-SYNC’s VRR (variable refresh rate) to synchronize to the focused window’s render rate; unfocused windows remain at the desktop’s fixed refresh rate until focused on.

G-SYNC only functions on one window at a time, and thus any unfocused window that contains moving content will appear to stutter or slow down, a reason why a variety of non-gaming applications (popular web browsers among them) include predefined Nvidia profiles that disable G-SYNC support.

Note: this setting may require a game or system restart after application; the “G-SYNC Indicator” (Nvidia Control Panel > Display > G-SYNC Indicator) can be enabled to verify it is working as intended.

G-SYNC Preferred Refresh Rate

“Highest available” automatically engages when G-SYNC is enabled, and overrides the in-game refresh rate selector (if present), defaulting to the highest supported refresh rate of the display. This is useful for games that don’t include a selector, and ensures the display’s native refresh rate is utilized.

“Application-controlled” adheres to the desktop’s current refresh rate, or defers control to games that contain a refresh rate selector.

Note: this setting only applies to games being run in exclusive fullscreen mode. For games being run in borderless or windowed mode, the desktop dictates the refresh rate.

G-SYNC & V-SYNC

G-SYNC (GPU Synchronization) works on the same principle as double buffer V-SYNC; buffer A begins to render frame A, and upon completion, scans it to the display. Meanwhile, as buffer A finishes scanning its first frame, buffer B begins to render frame B, and upon completion, scans it to the display, repeat.

The primary difference between G-SYNC and V-SYNC is the method in which rendered frames are synchronized. With V-SYNC, the GPU’s render rate is synchronized to the fixed refresh rate of the display. With G-SYNC, the display’s VRR (variable refresh rate) is synchronized to the GPU’s render rate.

Upon its release, G-SYNC’s ability to fall back on fixed refresh rate V-SYNC behavior when exceeding the maximum refresh rate of the display was built-in and non-optional. A 2015 driver update later exposed the option.

This update led to recurring confusion, creating a misconception that G-SYNC and V-SYNC are entirely separate options. However, 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.

Within its range, G-SYNC is the only syncing method active, no matter the V-SYNC “On” or “Off” setting.

Currently, when G-SYNC is enabled, the control panel’s “Vertical sync” entry is automatically engaged to “Use the 3D application setting,” which defers V-SYNC fallback behavior and frametime compensation control to the in-game V-SYNC option. This can be manually overridden by changing the “Vertical sync” entry in the control panel to “Off,” “On,” or “Fast.”



3069 Comments For “G-SYNC 101”

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m_staf
Member
m_staf

Hello,

I have been having much trouble with my G-sync intermittently working for seemingly no rhyme or reason for months. I have followed all of the recommended steps for setting up Gysnc and have a Gsync certified monitor (Asus TUF VG27A). Gsync WILL work for a few of the games on my computer such as Red Dead Redemption 2 and Rise of the Tomb Raider. I can tell that it is working because of the Gsync enabled badge appearing in the game and a noticeable improvement in tearing. Gsync will not however work in games like Battlefield V or World of Warcraft classic (it previously did when I first built my computer). I figured this may be due to improper in game settings on my end at first. However, when using the Nvidia pendulum demo, I have not once been able to select the Gsync box in the demo. There are no signs of Gsync working at all in the demo and it is accompanied by terrible frame rate tearing. I can select the Vsync option in the demo (if that means anything).
I have done a clean reinstall of the drivers, tried multiple monitors, display port cables, HDMI cables, etc, default Nvidia control pannel settings. Nothing has seemed to work at all! It is incredibly frustrating as I have combed forums and boards for months looking for a solution. It is also upsetting spending the extra money for a certified Gsync monitor and still having the issues. I usually have a dual monitor setup. One monitor is a freesync Acer XF270HUA and the other is the Asus previously mentioned. I have tried testing one monitor at a time with the same issues so I do not believe it to be the fault of having dual monitors.

All settings on nvidia control panel are default besides the following

Set up G-SYNC > Enable G-SYNC, G-SYNC Compatible > Enable for full screen mode.
Manage 3D settings > Max Frame Rate 162 FPS
Manage 3D settings > Vertical sync >ON

Do you have any ideas of what could be causing the issue or inconsistency?

Thank you for your time and help!

drameloide
Member
drameloide

The results show a consistent difference between the three methods across most refresh rates (240Hz is nearly equalized in any scenario), with V-SYNC OFF (G-SYNC + V-SYNC “Off,” to a lesser degree) appearing to have a slight edge over G-SYNC + V-SYNC. Why? The answer is tearing…

about this paragraph, you said gsync + vsync off have tearing issues and this is completely wrong if you are in range of gsync, differences between vsync on + gsync and vsync off + gsync is only the plus of input lag vsync offer you

tbhee
Member
tbhee

For AMD is it correct to set the framerate limiter through Radeon Chill Min and Max = cap?

And for a game that does have an ingame limiter would it be overkill to be using that as well
as Chill?

Gsyncmasterace
Member
Gsyncmasterace

Hey there 😀

Do you guys know if there is any difference between gsync and a fixed refresh rate with an unlimited framerate ( lets say 400 fps at 240hz ).

Agitatio
Member
Agitatio

Hello again, have another question to bother you with.

So I have 240Hz G-SYNC monitor, and I have G-SYNC and VSYNC enabled in NVCP.
I don’t trust in-game FPS limiters due to too much variance and some games having very weird frame pacing or just bad FPS limiters, which both require too much trial and error.

So considering that, I’m left with limiters like RTSS and NVCP. Which both should be equal by this point when it comes to input lag. So I was wondering if using those kind of limiters is still superior to having VSYNC engage when hitting ceiling, as they can still add up to 1 frame of additional input lag. And I also noticed that input lag difference is not that drastic in some of your comparison graphs for 240Hz with limit and without.

If FPS lock still advisable in my case, do you have a recommended “better safe then sorry / should affect 99.9% of cases” number to lock below refresh rate? Similar to your -3 and ULL overkill of -15(for 240Hz that is)?

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