Page 1 of 1

Problem with G-SYNC

Posted: 27 Dec 2018, 06:29
by Kaggewas
Hello everyone, I noticed long ago, when g-sync is turned on in some moments (most often the game loading), the mouse loses its smoothness and the screen starts to flicker a bit, are there ways to solve this?

https://youtu.be/5UCdPJWud0Q

Re: Problem with G-SYNC

Posted: 27 Dec 2018, 10:27
by jorimt
That's normal, and no, there isn't a solution.

Some loading screens have massive fps fluctuations while crunching assets, often dropping well below 30 FPS, and since G-SYNC effectively matches the refresh rate to the framerate (unlike standalone V-SYNC, where the refresh rate is constant, regardless of framerate), the mouse movement will reflect those very low refresh rates.

Re: Problem with G-SYNC

Posted: 27 Dec 2018, 14:53
by Kaggewas
jorimt wrote:That's normal, and no, there isn't a solution.

Some loading screens have massive fps fluctuations while crunching assets, often dropping well below 30 FPS, and since G-SYNC effectively matches the refresh rate to the framerate (unlike standalone V-SYNC, where the refresh rate is constant, regardless of framerate), the mouse movement will reflect those very low refresh rates.

It just annoys me ...
Does this happen on all G-SYNC monitors or on some?

Re: Problem with G-SYNC

Posted: 27 Dec 2018, 15:16
by RealNC
Kaggewas wrote:It just annoys me ...
Does this happen on all G-SYNC monitors or on some?
The mouse cursor getting refreshed at 30FPS happens on all monitors. If the monitor refreshes at 30Hz, you get a 30FPS mouse cursor.

The flickering only happens on TN monitors AFAIK. It does not happen on my IPS monitor.

One thing you can try is forcing vsync to OFF in the nvidia panel. This might reduce the problem.

Re: Problem with G-SYNC

Posted: 27 Dec 2018, 15:40
by jorimt
I have seen very minor flicker on my IPS in G-SYNC mode on some loading screens before, but it doesn't always occur; I can't find a pattern. It may be inversion-based (specific visual on-screen patterns or grayscale/colors on certain load screen) or perhaps due to slightly different G-SYNC "Minimum Refresh Range" implementation from driver to driver? Last time I really noticed this was on a Garry's Mod load screen years ago when I first got my display.

Also, while I haven't tested it thoroughly, yes, it's possible G-SYNC + V-SYNC "Off" could reduce flickering at super low refresh rates, as it should be allowed to tear in those instances instead of sync. Though this is pretty difficult to test in isolation, since it mostly occurs on load screens, is only obvious in certain games/scenarios, and usually for extremely brief periods of time.

Thankfully a very fringe issue.

Re: Problem with G-SYNC

Posted: 27 Dec 2018, 17:36
by Chief Blur Buster
I could probably confirm if this is inversion-artifact-related -- if I can view a sample of sufficiently high-resolution highspeed video:

Anybody with a Samsung Galaxy 9 with the 960fps high speed camera feature (which has 720p resolution in high speed video), may be able to do a macro focus on the screen, and film the flickering this way. Preferably in macro mode so I can see the pixels. If that can be done, I can definitively confirm if the flickering is an inversion artifact (interaction with the normal automatic LCD inversion process from erratic-length and/or ultralow-Hz refresh cycles).

Yes, a very fringe artifact that is not seen in normal gameplay, especially since frameates are often well above the GSYNC minimum if you've got a powerful GPU and a 240Hz GSYNC monitor.