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.”



3051 Comments For “G-SYNC 101”

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Sort by:   newest | oldest | most liked
Glarbstintenford
Member
Glarbstintenford

In NVCPL it suggests that using Ultra low latency mode minimizes input latency when both G-Sync + V-Sync is enabled.

I was curious if they mean having NVCPL V-sync set to “on” or the in-game V-sync set to “on” or both set to “on”?

Also curious how ‘minimal’ the input latency is compared to using G-Sync on + in-game V-Sync set to “off” + NVCPL V-Sync set to “on”?

Achilles68
Member
Achilles68

Hi!

I switched out my HDMI cable for a USB-C to DP cable to enable gsync on the 144hz screen connected to my laptop.
This also revealed all the other NVCP features laptops usually don’t have. Immediately I went to enable vsync + low latency mode.

However I could only choose between ‘off’ and ‘ultra’ for the latter. I put it on ultra and went ingame to see if things work. I got a big stutter every few seconds, it was really unplayable.

Therefore my question: Do I leave it off and set an ingame fps limiter at 141fps? Will this have the same results as LLM ‘on’ + vsync?

Bonus: Is there any way to make ‘on’ appear again?

Competitive
Member
Competitive

I have an asus vg248qe, pretty sure its not a freesync/gsync monitor. Ive been trying to play fortnite competitively and Idk whether its less input lag to play on above fps cap than my 144hz. I also have a crr set to 1750×1080 for stretch res, everything works no black bars but when I check nvidia control pannel theres no “display” in scaling. I dont seem to notice the input lag tho even if its on “gpu”. I have a gtx 1080 and 3600x (if that matters)

fury80
Member
fury80

I couldn’t find in your input lag tests. How much input lag difference is there when playing in these situations ?

1- 50fps-50hz gsync+vsync on 144hz monitor
2- 50fps-144hz no sync 144hz monitor or 240-360hz with very low 50 fps.

I’m asking this because i bought gsync compatible LG 27GL850 which has good gsync and response times performance compared to my Samsung C27HG70 however i feel like i’m having way more input lag compared to my no sync C27HG70 and honestly i don’t see any tearing with high refresh rate monitors outside of very specific moments, paterns in games. I feel like these gsync/freesync stuff is a bit of a gimmick and very heavy on monitors to do reliably. High refresh rate and black frame insertion more important i think.

Linerax
Member
Linerax

My monitor is currently an LG 32GK650F-B with original Freesync and is not certified G-Sync compatible yet from Nvidia. I am guessing my situation in using G-Sync + V-Sync is more if a wild card than if I were to use a monitor with native G-Sync, yes? But should I still try what have been suggested in this detailed report or any special advice for Freesync users?

wpDiscuz