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.”



3061 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
Yiox
Member
Yiox

Admittedly an edge case, but there are Souls-games which are 60 fps capped AND switch your refresh rate forcefully to 60 Hz – even if you set to “use highest available” in the driver.

For comparison:
Dark Souls 1 Remastered
IG Vsync off and set to driver app controlled.
Runs at 60 fps cap and lets you switch correctly to 165 Hz refresh rate, looks smooth without any issues.
As it runs fine I haven’t tried if forcing off Vsync or forcing it on would make a difference, but could be interesting comparing latency?

Dark Souls 2: SOTFS
IG Vsync is always on with no setting to change it when set to driver app controlled.
Runs at 60 fps cap and uses only 60 Hz refresh rate, looks smooth but likely has higher input lag because of Vsync?
Forcing Vsync off in the driver causes constant massive tearing in this game.
So might as well force Vsync on in the driver to ignore the game’s settings in case the devs messed up further stuff with it.
Can apparently fix it with 3rd party program “Special K” to run at higher refresh rate.

Dark Souls 3
IG Vsync is always on with no setting to change it when set to driver app controlled
Runs at 60 fps cap and uses only 60 Hz refresh rate, looks smooth but likely has higher input lag because of Vsync?
Forcing Vsync off in the driver causes constant massive tearing in this game.
So might as well force Vsync on in the driver to ignore the game’s settings in case the devs messed up further stuff with it.
Can apparently fix it with 3rd party program “Souls unsqueezed”(a variant of “Special K”) to run at higher refresh rate.

Capping to -3 fps below refresh rate (57 fps then) in DS2 and DS3 isn’t feasible as the game speed/logic is tied to it in both cases.
So in regards to the 3rd party solutions for DS2 and DS3: I wonder if getting the refresh rate fixed to 165 Hz and let the game run with forced Vsync off at 60 fps would provide better latency than the Vsync on (per application or driver forced)-state has now?
Or if just getting refresh rate fixed to 165 Hz and leaving Vsync on (either ingame or per driver) would improve latency?

Could you look into that if it’s worth messing with those 3rd party solutions in those games (and maybe if forced Vsync settings in DS1 make a difference)?

jesus
Member
jesus

Hi. I have ryzen 1600 (4.0Ghz), gtx 1070, 8x2gb 3600mhz ram, dell s2417dg (165hz), mechanical keyboard with report rate 1000hz, and same 1000hz in mouse. So i have games which i cant get stable or near stable 165fps (gta5, witcher, tomb raider, bo4 etc) most of them like 100-110fps with drops to 70-80, which method i should use? NVCP G-sync+V-sync ON (and v-sync off in game) which RTSS 162FPS, or simple g-sync (v-sync OFF in nvcp and in-game) due to fps is stable below monitor refresh rate? Which method i get most smooth and lowest input lag image? Thanks! (sorry for my english)

wonsong82
Member
wonsong82

I have 240hz monitor without g-sync. My pc is 8700k @5g + gtx1080 so i can get constant 300 fps in overwatch. Before I read your post, I never noticed tearing, but after, I was able to notice it when I look at it really really close. So as far as I understood, if I enable fast-sync, I theoretically get 1-2ms more input lag as opposed to g-sync with capped frame which isnt anything significant. Am I right? But how about if you’d compare it without any sync on? I have been playing at 240hz with constant 300fps without any sync. but after I enabled fast-sync, It seems my aim is little off when I play hitscan and I couldn’t figure out if it was the added input lag or just my feeling. I would appreciate if you can give me the expected increment input lag in numbers. I believe in numbers.

nheira0000
Member
nheira0000

I have a question .
How should I install nvidia with the pubg game?
I have pg279q and strix 1070ti

ynemis
Member
ynemis

First thanks for the amazing written article, it cleared up many questions I had. There are still some thing that I don’t fully understand.

As you made clear G-SYNC on + V-SYNC on + -3 FPS limit are the best settings for a tear free and low input lag solution. My question is about the RTSS fps limiter, if I use it in a game that runs at an average of 150 fps on a 165Hz G-SYNC monitor it makes sense to use the RTSS fps limiter because the framerate may spike up to above the maximal refresh rate of 165Hz causing input lag. Does the RTSS fps limiter also cause the additional 1/2 frame delay if the framerate stays below the 162 fps limit?

My second question is about the difference in input lag between G-SYNC on+ V-SYNC off + FPS uncapped vs. G-SYNC off + V-SYNC off + FPS uncapped. I want to play CSGO at the lowest input lag possible and I don’t mind tearing there. Does having G-SYNC enabled without V-SYNC, but playing above the max refreshrate add some additional input lag compared to turning G-SYNC off? I want to know if I should bother turning G-SYNC off every time I play competitive. Thanks a ton in advance!

wpDiscuz