[Guide] How to use RTSS's Scanline Sync to reduce stuttering, screen tearing and input lag on PC (alternative to Vsync, G-Sync and FreeSync)

[EeK9X]

I was asked, in the "Control PC performance thread", to do a write-up on how to use RTSS's Scanline Sync function. After writing a 7-page document, I figured that it would better serve the community as its own separate thread, since it can be applied to all games, and not just Control.

Special thanks to Unwinder, developer of RTSS (Rivatuner Statistics Server), and Mark Rejhon (mdrejhon), founder of Blur Busters and the one who suggested the implementation of Scanline Sync. Mark's thread and guides on the subject can be found here and here. I definitely recommend checking them out, as he is the absolute authority on all things related to motion blur and input lag.

This will be a very concise and non-technical explanation, as I am by no means an expert on the subject (for that, you need Chief Blur Buster). Still, I'll try to be as clear and didactic as possible.


Table of contents:

1. Introduction

1.1 What is Scanline Sync and what is it for?​

1.2 When is Scanline Sync most useful?​

1.3 What do I need to use Scanline Sync?​

1.4 What is RTSS (Rivatuner Statistics Server)?​

2. Setting up

2.1 Basic configuration (optional)​

2.1.1 Disable fullscreen optimizations​

2.1.2 Set "Power management mode" to "Prefer maximum performance" (Nvidia only)​

2.2 Configuring the OSD (on-screen display)​

2.3 Editing RTSS's Global configuration file​

2.4 Adding individual game profiles​

3. Using Scanline Sync

3.1 Calibrating the tear line​

3.2 Editing the game's profile to enable Scanline Sync​

4. Extra tips

4.1 SyncFlush (0, 1 or 2)​

4.2 Fast Sync and Enhanced Sync​

4.3 Easier way to visualize tear lines​

4.4 Running games at double your display's refresh rate​

5. FAQ (see threadmark)

5.1 I have a G-Sync/FreeSync-compatible monitor, should I use Scanline Sync?​

5.2 Should I disable Vsync when using Scanline Sync?​

5.3 Should I leave the frame rate uncapped when using Scanline Sync?​

5.4 I tried moving the tear line away, but can't make it disappear.​

1. Introduction


1.1 What is Scanline Sync and what is it for?

Scanline Sync is a software-based solution to reducing screen tearing, while resulting in lower input lag than regular Vsync. Because of the way motion is perceived by the human eyes, it also helps eliminate erratic stutters on non-variable refresh rate (VRR) panels - that is, if your GPU can maintain frame rates that are constantly above your display's actual refresh rate (something that is of utmost importance, as you will get frame time spikes/stutters otherwise).

Basically, it's a platform-agnostic alternative to Nvidia's G-Sync or AMD's FreeSync, with the difference being that those adaptive sync technologies work with fluctuating frame rates, since they also require VRR panels, which sync the refresh rate to the rendering of the frames.


1.2 When is Scanline Sync most useful?

Scanline Sync works best when the GPU load is low.

This means that less powerful GPUs or more demanding titles won't benefit from Scanline Sync. Its main requirement is for games to be constantly running at frame rates higher than your display's refresh rate. If your TV or monitor is 60Hz, games need to run at 60fps or more.

Even occasional dips in frame rate can cause frame time spikes (perceived as stuttering), when using Scanline Sync. Ideally, your GPU should be able to match frame rates to the refresh rate 99.9% of the time. Stutters caused bv drops to the 90% to 95% range can be alleviated by using RTSS's Scanline Sync in conjunction with Nvidia's Fast Sync or AMD's Enhanced Sync (see 4.2 Fast Sync and Enhanced Sync).


1.3 What do I need to use Scanline Sync?

In order to use Scanline Sync, you will need only one thing: RTSS (Rivatuner Statistics Server). It works with any GPU (given that it's capable of maintaining high frame rates, as previously mentioned) and display, on any game, regardless of its graphics API (DX11, DX12, Vulkan, etc.).


1.4 What is RTSS (Rivatuner Statistics Server)?

RTSS (Rivatuner Statistics Server) is a frame rate monitoring and limiting software. It's included with all versions of MSI's Afterburner overclocking utility, and although it's also available as an individual download, I recommend installing both programs, since RTSS relies on AB for the on-screen display (OSD), even if you don't use any of the latter's other functions.

Download RTSS's latest version (7.2.3 Beta 3 - Build 20636)


2. Setting up


2.1 Basic configuration (optional)

Even though this step isn't required for Scanline Sync, I'd still recommend to do the following for all PC games:


2.1.1 Disable fullscreen optimizations

1. Right-click the game's EXE and select "Properties";
2. In the "Compatibility" tab, select (mark) the checkbox labeled "Disable fullscreen optimizations";
3. Additionally, click on the button labeled "Change high DPI settings" and make sure that the checkbox labeled "Override high DPI scaling behavior" is also selected (marked) and that scaling is set to be performed by "Application". Click on "OK";
4. Click on "Apply", then "OK".

Notes:

There was an option to globally disable fullscreen optimizations, as confirmed by a Microsoft employee here, but it has been unavailable since the Windows 10 Fall Creators Update (1709).

Redditor u/Skymirrh made an app to "bulk disable" fullscreen optimizations. In that thread, the same MSFT employee said that they were hoping to make that tool obsolete at some point. That was almost two years ago.


2.1.2 Set "Power management mode" to "Prefer maximum performance" (Nvidia only)

1. Open NVIDIA Control Panel (NVCP), by right-clicking on your desktop and selecting "NVIDIA Control Panel";
2. On the left side menu, click on "Adjust image settings with preview";
3. On the right side menu, check "Use the advanced 3D image settings", then click on "Apply" in the bottom right corner of the window;
4. Click on "Take me there", right next to "Use the advanced 3D image settings", or click on "Manage 3D settings on the left side menu";
5. Under "Manage 3D settings", click on "Program Settings", then "Add";
6. Select the game's EXE in the "Recently used" list of programs (if it's not there, go to "Browse" and navigate to the game's folder);
7. Make the following changes under "Specify the settings for this program" (Feature > Setting):
   • Power management mode > Prefer maximum performance
8. Click on "Apply" in the bottom right corner of the window to save your settings.

Notes:

I prefer to do that on a case-by-case basis, instead of setting it globally. My global power management mode is set to "Optimal power", so that the GPU doesn't run at full throttle 100% of the time.

Additionally, I also set the new "Low Latency Mode" to "On". That setting was formerly known as "Maximum pre-rendered frames", and "On" corresponds to "1". You can also try turning it off (which would then correspond to "3"), but I strongly advise against setting it to "Ultra" ("0"), as you'll be eliminating the number of pre-rendered frames that can be cached entirely, and that can cause even more sutters.

Lastly, for games that run in DX11 or below, I also tend to use Nvidia's Fast Sync in conjunction with RTSS's Scanline Sync, but I'll address that option at the end of this guide.

Edit: I've only owned Nvidia GPUs and don't know if there's a similar setting for AMD cards. However, as I stated, this step isn't required for Scanline Sync, and I only included as part of my personal recommended optimizations.


2.2 Configuring the OSD (on-screen display)

Follow this guide to configure MSI Afterburner and RTSS to display the appropriate information on the screen. Make sure that both "Framerate" and "Frametime" are selected under "Monitoring", with the checkbox "Show in On-Screen Display" also selected (marked).

I recommend having "Framerate" display as "text" and "Frametime" display as "text, graph" for better visualization. That way, it's easier to notice any frame pacing issues (ideally, your frametime line should remain flat, meaning that frame times are constant - less stuttering).

Also, on RTSS, confirm that "Show own statistics" is set to "On" (thanks, Shocchiz). If you're having issues with the OSD, causing games to crash, you can try changing the "On-Screen Display rendering mode" from "Raster 3D" to "Vector 2D" (thanks, Jazzem).


2.3 Editing RTSS's Global configuration file

You need to add "SyncHotkeys=1" to your RTSS's global configuration file to enable shortcuts, so that you can move the tear line up and down in-game using keyboard shortcuts.

1. After installing RTSS, locate its "Profiles" folder (by default: "C:\Program Files (x86)\RivaTuner Statistics Server\Profiles");
2. Right-click on the file named "Global", choose "Open with" and select Notepad;
3. Under "[Framerate]", include the line "SyncHotkeys=1";
4. Click on "File", then "Save" (or press Ctrl + S), before closing Notepad.

This is what the "[Framerate]" part of your Global CFG file should look like:

[Framerate]
Limit=0
LimitDenominator=1
SyncHotkeys=1
LimitTime=0
SyncScanline0=0
SyncScanline1=0
SyncPeriods=0

2.4 Adding individual game profiles

On RTSS, click on the green button labeled "Add", located in the bottom left corner of the window, then navigate to the game's main folder and select its EXE.

RTSS's default settings (and functions) should work for most games, but for Scanline Sync, you'll need to enable a few specific settings in the individual profiles of each game.

Using Notepad, open the game's CFG file, located inside RTSS's "Profiles" folder. Add the necessary information so that the settings under "[Framerate]" look exactly like this:

[Framerate]
Limit=0
LimitDenominator=1
LimitTime=0
SyncFlush=1
SyncScanline0=0
SyncScanline1=0
SyncPeriods=0

Additionaly, you have to include "SyncInfo=1" to the "[OSD]" section. You can also do it globally, as with the previous step, if you don't mind displaying unecessary information when not using Scanline Sync (thanks, Shocchiz).


3. Using Scanline Sync


After all prepping is done, it's time to finally use Scanline Sync.

As I said earlier, the purpose of Scanline Sync is to achieve the same results as other adaptive sync solutions (no visible screen tearing and minimal stuttering), while adding no input lag. The way it does that is by limiting the game's frame rate to match your display's refresh rate.

The "catch" is that it doesn't completely eliminate tearing - there will still be a tear line or two, depending on your settings. However, with RTSS, you'll be able to move those tear lines away from the screen (using the previously enabled keyboard shortcuts), making them invisible.

The first step is to calibrate the tear line, so that it's outside of the screen's visible area.


3.1 Calibrating the tear line

1. Disable all forms of Vsync, both in-game and outside of it (on NVCP);
2. Open MSI Afterburner and RTSS (RTSS should start automatically after opening AB);
3. With RTSS running in the background, start the game;
4. Strafe and/or move the camera around - you'll notice a single tear line, that may be relatively stable or more erratic/jittery, depending on the game;
5. Hold Ctrl + Shift and use the up and down arrow keys to move the tear line up and down. The longer you press and hold the arrow keys, the faster the tear line will move;
6. In the OSD, notice how the number related to "Sync line 0" changes as you move the tear line;
7. Move the tear line and try to position it in such a way that it ends up outside of the visible area of your screen - or, at least, in the least obtrusive part (top or bottom);
8. Mark down the number displayed after "Sync line 0" after the tear line is hidden - you'll use it to save the correct information to your game's profile on RTSS.

3.2 Editing the game's profile to enable Scanline Sync

1. The number displayed after "Sync total", in the OSD, is related to the total number of "lines" your display has. It changes depending on your current resolution.
2. To obtain the Scanline Sync number, you subtract the calibrated "Sync line 0" number from the "Sync total".
3. You then add the resulting number as a negative index to RTSS (under "Scanline sync"), or directly to the game's CFG ("SyncScanline0=-XXX", where "XXX" is the resulting number).

Example:

On 3840 x 2160 resolution (4K), the Sync total is 2250. In my experience, for most games running in 4K, the tear line disappears with Sync line 0 set to 2110. 2250 - 2110 = 140. Therefore, you type in "-140" in RTSS's box dedicated to Scanline sync, or simply edit the game's CFG file to include "SyncScanline0=-140".

Important: you must use negative numbers. Chief Blur Buster explains why here.


4. Extra tips


4.1 SyncFlush (0, 1 or 2)

Flushing is used to make Scanline Sync more accurate. "SyncFlush=1" is the recommended setting for most games. "0" will cause the tear line to become unstable and jittery. "2" can be selected when GPU usage is incredibly low (~30%) - recommended for older games.


4.2 Fast Sync and Enhanced Sync

In scenarios where the frame rate can't be maintained above the refresh rate 100% of the time, with frame rate dipping to the 90%-95% range (54fps-57fps out of 60fps), Scanline Sync can be used in conjunction with Nvidia's Fast Sync or AMD's Enhanced Sync.

Important: Fast Sync only works with games using DirectX 11 and below (DX11, DX10, DX9). It does not support DirectX 12, OpenGL or Vulkan (source). Enhanced Sync works with games using DirectX 9, DirectX 10, DirectX 11, DirectX 12 and Vulkan. It does not support OpenGL (source).

For how to enable Fast Sync on Nvidia Control Panel, see 2.1.2 Set "Power management mode" to "Prefer maximum performance" and follow all the steps there, but instead of changing "Power management mode" during step #7, change "Vertical Sync" to "Fast".


4.3 Easier way to visualize tear lines (thanks, Ravio-li)

RTSS has a feature that allows you to enable a frame color indicator, making it easier to visualize the tear lines, during calibration. Here's how to do it:

1. Open RTSS and click on the blue button labeled "Setup" in the center bottom part of the window;
2. In the "General" tab, under "FCAT properties", select (mark) the checkbox labeled "Enable frame color indicator";
3. In the drop-down menu, select your preferred visualization method (Ravio-li recommends "2 bars", so that "you can see where the scanline is and if the frame pacing is regular").

4.4 Running games at double your display's refresh rate (thanks, Ravio-li)

I purposely left this out of my original write-up because I still haven't personally tested it, and I deemed it a bit too complicated for a beginner's tutorial. Per @Ravio-li's suggestion, I'll include the information here, as an extra tip, quoting him and Chief Blur Buster directly:

You can run games at double your monitor refresh rate if you set the scanline sync to x2 (click on it once). This will result firstly in 2 visible scanlines, one somewhere in the middle of the screen. You can get rid of it by using scanline sync together with nvidia fastsync. If everything is correct and you have the frame color indicator selected to 2 bars, one of the 2 bars will never appear -> you skip every other frame and should get better latency.

Also the x/2 half refresh mode is very useful for games that can't get a stable framerate or are below the freesync range, if you have a monitor with it.

Click to shrink...

What about SyncScanLine1 for twice framerate versus refresh rate?

- If unfamiliar with this, keep SyncScanLine1 setting to 0. Worry only about one tearline (SyncScanLine0 or via GUI)

- Even if you do this, please do the easy stuff first before attempting this

If your game is ultra-low GPU (e.g. Quake Live or CS:GO) combined with motion blur reduction, this can reduce strobe lag a further (e.g. 240fps at 120Hz, or 200fps at 100Hz). First, calibrate using VSYNC OFF. You may use two tearlines with Enhanced Sync or Fast Sync -- but not with VSYNC ON (that will frame-throttle you badly). Calibrate the middle tearline to middle of screen (slightly above middle is ideal, to keep it equidistant with the bottommost tearline, but position of middle tearline matters less than the bottommost tearline) but focus on carefully calibrating the bottommost tearline to stay permanently above bottom edge of screen. Ideally, they should be signal-equidistant from each other (half Vertical Total apart, taking into account of VBI versus visible vertical resolution). But this is less critical than keeping the bottommost tearline permanently above bottom edge of screen, in order to avoid those lag spikes during Fast Sync and Enhanced Sync.

Click to shrink...

 

[OddSock]

Incredible post. Thanks! Will test it out. :)

 

[BeI]

Scan line sync was pretty amazing when I had it working properly in Oblivion and Star Wars BF2 (old version) at 30 fps. Felt so smooth, especially without the input lag of V sync. I swear using that for a 30 fps cap felt better than freesync at 30fps. It's just too bad it seemed to need quite a gpu overhead.

 

[Deleted member 29237]

Great guide - thanks very much!

 

[b0uncyfr0]

Been waiting for this - im surprised it took so long for it to happen.Scanline sync is simply amazing for peeps still on 60 hz, have abit of headroom and hate tearing.

 

[Vex]

Sugoi! Arigatou.

 

[Deleted member 12790]

So then this would basically be the equivalent of hblank sync from old consoles?

Time really is a circle...

 

[shark97]

i mean cool but, my eyes glaze over whenever you start having to manually edit text files (looking at you, retropi)

 

[Md Ray]

Thank you so much for writing this. I will give this a try.

 

[Jazzem]

Fantastic work, thanks so much for putting this together :) Been using RTSS for a while but never exactly knew what scanline sync was, will definitely be trying it now. Moving the year line out of viability is so clever!

I was often using the frame rate limit to get even frame pacing but have found the occasional game it doesn't play nice with. Stardew Valley's frame rate for instance kept jumping between 50-60fps. Wondering now if the scanline sync would be a better fit there

Also have found the on screen display in its 3D variants can cause crashes, I recently had Spark the Electric Jester keep crashing until I changed it to the 2D option

 

[Patitoloco]

I tried this some time ago, and I managed to "move" the tearing, I never managed to completely vanish it out of the screen. Maybe I'll give it another shot with your guide, thanks :)

 

[Dictator]

I tried this some time ago, and I managed to "move" the tearing, I never managed to completely vanish it out of the screen. Maybe I'll give it another shot with your guide, thanks :)

Click to shrink...

YOu need an incredibly low GPU utilisation or an incredibly high and perfectly consistent framerate for it move it offscreen at all times in my experience.

We wanted to cover this on the channel, but is extremely specific in its use case. Very very very specific.

 

[Midee]

So I imagine this would be really good for emulators? Or is latency already covered when you enable GPU sync?

 

[Zoon]

Bookmarked.
I don't know how well it'll work since most of the times I'm CPU limited.

 

[Patitoloco]

YOu need an incredibly low GPU utilisation or an incredibly high and perfectly consistent framerate for it move it offscreen at all times in my experience.

We wanted to cover this on the channel, but is extremely specific in its use case. Very very very specific.

Click to shrink...

That would explain why it worked even worse with more demanding games when I tested it.

 

[Ravio-li]

A few tips I haven't spotted while quickly glancing over the first post:
Activate the frame color indicator in the RTSS options. I set it to 2 bars, so you can see where the scanline is and if the framepacing is regular.

You can run games at double your monitor refresh rate if you set the scanline sync to x2 (click on it once). This will result firstly in 2 visible scanlines, one somewhere in the middle of the screen. You can get rid of it by using scanline sync together with nvidia fastsync. If everything is correct and you have the frame color indicator selected to 2 bars, one of the 2 bars will never appear -> you skip every other frame and should get better latency.

Also the x/2 half refresh mode is very useful for games that can't get a stable framerate or are below the freesync range, if you have a monitor with it.

 

[dgrdsv]

Scanline sync is a great option for those who care about input lag more than they care about occasionally teared frame. It's important to understand that you won't be able to completely get rid of tearing with scanline sync - but it's possible to make it invisible most of the time. It's somewhat of a middle ground between playing without any kind of vsync and h/w adaptive sync options.

But as Dictator pointed out, you'll generally have to keep your GPU usage below ~67% at all times for it to work - and even then you'll see some teared frames here and there. I use it mostly to get rid of excessive input lag in some older titles, newer games and those where input lag isn't a big issue are better off with a regular vsync or even without vsync IMO.

 

[Shocchiz]

3.1 Calibrating the tear line

1. Disable all forms of Vsync, both in-game and outside of it (on NVCP);
2. Open MSI Afterburner and RTSS (RTSS should start automatically after opening AB);
3. With RTSS running in the background, start the game;
4. Strafe and/or move the camera around - you'll notice a single tear line, that may be relatively stable or more erratic/jittery, depending on the game;
5. Hold Ctrl + Shift and use the up and down arrow keys to move the tear line up and down. The longer you press and hold the arrow keys, the faster the tear line will move;
6. In the OSD, notice how the number related to "Sync line 0" changes as you move the tear line;
7. Move the tear line and try to position it in such a way that it ends up outside of the visible area of your screen - or, at least, in the least obtrusive part (top or bottom);
8. Mark down the number displayed after "Sync line 0" after the tear line is hidden - you'll use it to save the correct information to your game's profile on RTSS.

Click to shrink...

Thanks for the info and the thread.
I didn't know you could move the line with the arrow keys.
But I can't find the Sync line 0 info in the osd, where is it? I followed you instructions, but I have no Sync line info in the osd, nothing at all.
What I'm doing wrong?

EDIT: found the problem. You have to enable the "Show own statistics" setting in RTSS. Maybe you should add it to the guide, it's off by default.
EDIT 2: you also need to add "SyncInfo=1" in the [OSD] section (not in the [Framerate] section) of the "Global" file

 

[Shocchiz]

A few tips I haven't spotted while quickly glancing over the first post:
Activate the frame color indicator in the RTSS options. I set it to 2 bars, so you can see where the scanline is and if the framepacing is regular.

Click to shrink...

Quoting because it's really easier if you do this.
Nice advice.

 

[ThreepQuest64]

Scanline Sync works best when the GPU load is low.

Click to shrink...

Too bad. I usually set my graphics setting to maximize my GPU performance. And if I still have headroom I increase the resolution. So basically in any modern game I simply don't have a low GPU load.

Thanks for the write up anyways!

 

[Einherjer]

Works incredibly well for me in control to cap the game at perfect smooth 30 fps, -20 was allrdy enough to make the tearline disappear (dx12 +max prerendered frames 1) and i only ever saw it again when my gpu was maxed but there was never any stutter even then.

 

[Dreams-Visions]

Great thread.

 

[ShinUltramanJ]

Awesome post! I'm going to have to try it out because Enhance Sync remains busted.

 

[b0uncyfr0]

EDIT: found the problem. You have to enable the "Show own statistics" setting in RTSS. Maybe you should add it to the guide, it's off by default.
EDIT 2: you also need to add "SyncInfo=1" in the [OSD] section (not in the [Framerate] section) of the "Global" file

Click to shrink...

Thank you very much! I wasn't sure if I was doing something wrong.

I will try 50 fps for control, perhaps I can rid of the tearing completely

Also control + up/down or shift + control +up/down doesn't do anything. Is there another setting for this? I've double checked and the hotkey setting is under my global conf.

 

[Shocchiz]

Thank you very much! I wasn't sure if I was doing something wrong.

So I guess we can't use scan line whilst capping the fps?

Click to shrink...

You are welcome, I'm glad I helped.

It's not needed to cap the framerate, but I don't know if it's "wrong" to cap it.

In the end what I do is setting scanline sync, then leave the vsync "let the application decide" option in the global settings (nvidia or amd), so while ingame if i have vsync on I have traditional vsync (no tearing), if off, I have scanline sync (less input lag).

 

[Shocchiz]

I have another question: are individual game profiles necessary if we use the default syncflush=1?
I didn't notice any benefit in setting an individual game profile.

 

[Shocchiz]

Also control + up/down or shift + control +up/down doesn't do anything. Is there another setting for this? I've double checked and the hotkey setting is under my global conf.

Click to shrink...

It's control + shit (at the same time) + up/down (3 keys)
I strongly suggest to activate the frame color indicator, see above.

 

[SiG]

Are there directions for power management mode on AMD cards? Most of the directions given are Nvidia centric.

 

[Shocchiz]

Are there directions for power management mode on AMD cards? Most of the directions given are Nvidia centric.

Click to shrink...

I think you can skip the power management part without regrets, it's not at all needed in my tests. Just try.

 

[b0uncyfr0]

Ive been testing with Control (DX11) for about an hour and it basically i cannot get rid of the tearing with scan line. At 60 fps - it fluctuates a lot and ive tried a lot of different scanline ranges..

Surprisingly FastSync does a good job with vsync as internally its broken (only allows double buffering)

 

[Ifrit]

I'd love Digital Foundry to do a video of this, with some nice video and lag comparisons.

 

[EeK9X]

Tried editing the OP to include this FAQ, but ran into some kind of limitation, as it was giving me an error message when saving the changes (likely due to its already gargantuan size). So, I'm adding the FAQ here, as a threadmark.


5. FAQ


5.1 I have a G-Sync/FreeSync-compatible monitor, should I use Scanline Sync?

No, use G-Sync/FreeSync, instead. Scanline Sync is a workaround for those playing on non-VRR (variable refresh rate) displays, such as most TVs and monitors.


5.2 Should I disable Vsync when using Scanline Sync?

Yes, you should disable Vsync in-game and at the driver level (using your GPU's control panel). Scanline Sync is a low input lag alternative to regular Vsync, so enabling both solutions will cause issues. The same goes for Adaptive Sync (full or half refresh rate).

You can, however, use Nvidia's Fast Sync or AMD's Enhanced Sync in conjunction with RTSS's Scanline Sync, to improve the results even further (see 4.2 Fast Sync and Enhanced Sync).


5.3 Should I leave the frame rate uncapped when using Scanline Sync?

Yes. Scanline Sync is, essentially, frame rate limiting. Because of that, you need to run all games with an uncapped frame rate to benefit from it. Scanline Sync will try to match your frame rate to your display's refresh rate, so there's no need to cap the frame rate in-game or use an external fps limiter, such as RTSS's own solution or Nvidia Inspector.


5.4 I tried moving the tear line away, but can't make it disappear.

Even when using only one tear line ("SyncScanLine1=0"), there's still a chance that tearing will occur, regardless if the main tear line (the one that you can move around) is "hidden".

This usually happens when your GPU can't handle a stable frame rate, and fps dips below your display's refresh rate. You can either try to live with the occasional screen tearing (if it's not too distracting and doesn't occur that often) or reduce the game's graphical settings and/or render resolution. You can also try to use Fast Sync or Enhanced Sync in conjunction with Scanline Sync, as documented in 4.2 Fast Sync and Enhanced Sync.

Alternatively, you can skip Scanline Sync altogether and use Fast Sync or Enhanced Sync while capping/limiting the frame rate through RTSS. It should introduce up to one frame of delay, compared to Scanline Sync's almost zero, but it's still better than external and, sometimes, even in-game fps limiters (that introduce two or more frames of delay). I explain how to do it, in detail, here, and will try to update this post and add a threadmark when I have the chance.

 

[EeK9X]

Thank you for the kind words, everyone!

I hope that this will come in handy for those of you who also play PC games on TVs and regular monitors. It's a good workaround until VRR becomes more prevalent, or new GPUs with HDMI 2.1 come out.

I edited the OP with some of your suggestions, and also added a FAQ in a threadmark. I'm planning on adding another threadmark with a different method of frame rate limiting, as soon as I have the time.

Scan line sync was pretty amazing when I had it working properly in Oblivion and Star Wars BF2 (old version) at 30 fps. Felt so smooth, especially without the input lag of V sync. I swear using that for a 30 fps cap felt better than freesync at 30fps. It's just too bad it seemed to need quite a gpu overhead.

Click to shrink...

YOu need an incredibly low GPU utilisation or an incredibly high and perfectly consistent framerate for it move it offscreen at all times in my experience.

We wanted to cover this on the channel, but is extremely specific in its use case. Very very very specific.

Click to shrink...

That would explain why it worked even worse with more demanding games when I tested it.

Click to shrink...

Scanline sync is a great option for those who care about input lag more than they care about occasionally teared frame. It's important to understand that you won't be able to completely get rid of tearing with scanline sync - but it's possible to make it invisible most of the time. It's somewhat of a middle ground between playing without any kind of vsync and h/w adaptive sync options.

But as Dictator pointed out, you'll generally have to keep your GPU usage below ~67% at all times for it to work - and even then you'll see some teared frames here and there. I use it mostly to get rid of excessive input lag in some older titles, newer games and those where input lag isn't a big issue are better off with a regular vsync or even without vsync IMO.

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Too bad. I usually set my graphics setting to maximize my GPU performance. And if I still have headroom I increase the resolution. So basically in any modern game I simply don't have a low GPU load.

Thanks for the write up anyways!

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Yeah, I tried my best to make it perfectly clear in the OP that Scanline Sync is a good solution only when you have a bit of GPU overhead (mentioned in the first two items of the "Introduction"). I'll probably add yet another disclaimer in a future update.

However, have you all played with Scanline Sync recently? I tested it when it was first released, early last year, and noticed that it only worked as intended for really old games or titles that weren't demanding at all. I'm talking max GPU utilization of around 30%.

Because of that, I basically wrote it off, and kept using my tried-and-true method of fps limiting via RTSS, combined with Fast Sync. It worked wonders, but obviously just for games running in DX11 or below. Only recently I decided to give Scanline Sync another go, and saw a massive improvement in the results.

RTSS has received quite a few updates since Scanline Sync was first introduced, and Unwinder has been working tirelessly to improve its implementation even further. In my experience, it has paid off, especially when it's possible to pair it with Fast Sync. But even on games that don't run in DX11, such as the recent Wolfenstein: Youngblood (Vulkan), Scanline Sync worked flawlessly, both in 4K @ 60Hz and 1440p @ 120Hz, with all settings maxed out, on a 1080 Ti.

It seems that the overhead required for Scanline Sync has been reduced significantly, and if you can at least maintain a frame rate that corresponds to your display's refresh rate (not with tens of fps to spare, like before), it will work, with no tearing or frame time spikes.

Alex, I'd love to see you and John tackle software-based G-Sync/FreeSync alternatives for PC gaming, and even suggested that to you both on Twitter, a while back. I don't think it's as niche a solution as it sounds, especially when tons of users are playing PC games on their TVs, nowadays, and most are dealing with high input latency or screen tearing without knowing of a better solution than Vsync on/off.

It would be great to educate more people on the subject, and perhaps even push Nvidia to finally implement Fast Sync for other graphics APIs (if AMD can do it with Enhanced Sync, why can't they?). HDMI 2.1 is still far from being widely available (no sources support it, and there's still no word of the next generation of GPUs), and even owners of 2019 LG OLED models, like myself, will have to wait until DisplayPort 1.4 to HDMI 2.1 adapters become available - that is, if they even work with VRR TVs at all. It's all a mystery, for now, and will be at least late 2020.

i mean cool but, my eyes glaze over whenever you start having to manually edit text files (looking at you, retropi)

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It's just two CFG files (one, if you plan on using RTSS's Scanline Sync for all games). Not that big of a deal. :)

Fantastic work, thanks so much for putting this together :) Been using RTSS for a while but never exactly knew what scanline sync was, will definitely be trying it now. Moving the year line out of viability is so clever!

I was often using the frame rate limit to get even frame pacing but have found the occasional game it doesn't play nice with. Stardew Valley's frame rate for instance kept jumping between 50-60fps. Wondering now if the scanline sync would be a better fit there

Also have found the on screen display in its 3D variants can cause crashes, I recently had Spark the Electric Jester keep crashing until I changed it to the 2D option

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Thank you!

Limiting the fps via RTSS and enabling Fast Sync was my go-to solution before the implementation of Scanline Sync improved considerably (which only happened in the last few months). You should definitely try it for Stardew. Just make sure to disable all forms of Vsync, unless you'd like to try Scanline Sync with Fast Sync/Enhanced Sync.

Also, thanks for the suggestion, I added it to the OP. And yeah, that can happen with a few select games.

So I imagine this would be really good for emulators? Or is latency already covered when you enable GPU sync?

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Scanline Sync will always introduce less input lag than traditional Vsync. Even if you just use RTSS to limit the frame rate (without enabling Scanline Sync), that'll still introduce less input lag than the alternatives (Nvidia Inspector or the in-game limiter), in most cases.

Bookmarked.
I don't know how well it'll work since most of the times I'm CPU limited.

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The article that I linked above mentions that RTSS is a "CPU-level FPS limiter". If you're CPU-limited, perhaps it won't work as well, but it doesn't hurt to try it and see for yourself!

A few tips I haven't spotted while quickly glancing over the first post:
Activate the frame color indicator in the RTSS options. I set it to 2 bars, so you can see where the scanline is and if the framepacing is regular.

You can run games at double your monitor refresh rate if you set the scanline sync to x2 (click on it once). This will result firstly in 2 visible scanlines, one somewhere in the middle of the screen. You can get rid of it by using scanline sync together with nvidia fastsync. If everything is correct and you have the frame color indicator selected to 2 bars, one of the 2 bars will never appear -> you skip every other frame and should get better latency.

Also the x/2 half refresh mode is very useful for games that can't get a stable framerate or are below the freesync range, if you have a monitor with it.

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Thank you for the suggestions. Added them both to the OP.

Thanks for the info and the thread.
I didn't know you could move the line with the arrow keys.
But I can't find the Sync line 0 info in the osd, where is it? I followed you instructions, but I have no Sync line info in the osd, nothing at all.
What I'm doing wrong?

EDIT: found the problem. You have to enable the "Show own statistics" setting in RTSS. Maybe you should add it to the guide, it's off by default.
EDIT 2: you also need to add "SyncInfo=1" in the [OSD] section (not in the [Framerate] section) of the "Global" file

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That's weird, that setting was enabled by default on my installation of RTSS. Are you using the latest version?

And you're right, I missed the part where you have to add "SyncInfo=1" to the "[OSD]" section, either in the Global CFG file or in a per-game basis. I'll edit the OP to include that information, thanks for the heads-up!

Works incredibly well for me in control to cap the game at perfect smooth 30 fps, -20 was allrdy enough to make the tearline disappear (dx12 +max prerendered frames 1) and i only ever saw it again when my gpu was maxed but there was never any stutter even then.

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Glad to hear that! Are you rendering Control in 1080p? When rendering in 1080p, -50 was the sweet spot, for me.

Also control + up/down or shift + control +up/down doesn't do anything. Is there another setting for this? I've double checked and the hotkey setting is under my global conf.

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As Shocchiz pointed out, you need to hold Ctrl and Shift at the same time, then press the up and down arrow keys to move the tear line accordingly.

It's not needed to cap the framerate, but I don't know if it's "wrong" to cap it.

In the end what I do is setting scanline sync, then leave the vsync "let the application decide" option in the global settings (nvidia or amd), so while ingame if i have vsync on I have traditional vsync (no tearing), if off, I have scanline sync (less input lag).

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No need to cap the frame rate through other methods, as Scanline Sync is, essentialy, frame rate limiting. Also, you have to disable all forms of Vsync in order for it to work - both in-game and at the driver level (Nvidia or AMD GPU control panels).

I included that information in the new FAQ.

I have another question: are individual game profiles necessary if we use the default syncflush=1?
I didn't notice any benefit in setting an individual game profile.

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Individual profiles are required if you don't plan on using Scanline Sync for all games. I sometimes use RTSS simply as an fps limiter or monitoring software, so I prefer to make minimal changes globally.

Are there directions for power management mode on AMD cards? Most of the directions given are Nvidia centric.

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Sorry, I don't own an AMD card, so I don't know for sure. As Shocchiz mentioned, that step is not required for Scanline Sync, so you can just skip it. I also edited the OP to make that more clear.

Ive been testing with Control (DX11) for about an hour and it basically i cannot get rid of the tearing with scan line. At 60 fps - it fluctuates a lot and ive tried a lot of different scanline ranges..

Surprisingly FastSync does a good job with vsync as internally its broken (only allows double buffering)

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Take a look at the newly added FAQ to make sure that you have the correct settings. Can't have any form of Vsync enabled (in-game or at the driver level), and the game's frame rate needs to be unlocked/uncapped.

What are your specs? On which resolution is Control being rendered? I posted quite a few specific recommendations for that game in the dedicated PC performance thread (including my own RTSS's CFG files), you should check it out. Quote me there with the answers to my questions and I'll definitely help you if I can.

I'd love Digital Foundry to do a video of this, with some nice video and lag comparisons.

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Same here. Please, Alex and John? :)

 

[Deleted member 20831]

Great one stop guide to use Scanline Sync!

But requires a lot of effort to set this up with hard prerequisites for the Scanline Sync to work properly, a point which is reached to an approximate level with FPS set very close and slightly lower than the monitor's actually refresh rate in decimals before enabling Vsync.

 

[Shocchiz]

Also, you have to disable all forms of Vsync in order for it to work - both in-game and at the driver level (Nvidia or AMD GPU control panels).

Individual profiles are required if you don't plan on using Scanline Sync for all games. I sometimes use RTSS simply as an fps limiter or monitoring software, so I prefer to make minimal changes globally.

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Thanks for your reply.

I'd like to point out that I'm not 100% sure disabling vsync at driver level is required.
I mean, vsync HAS to be off for scanline to work, but that can be done using game settings in my testings. I haven't notice a difference disabling it at driver level too.

I have both nvidia (2080ti) and amd (Vega56), and I use the default driver setting (=let the game decide) and here's what I do:
- at first I set a scanline value in RTSS. If value is 0 scanline is off, so disabling vsync ingame will mean no vsync (tearing, uncapped framerate)
- then I set vsync on or off ingame, depending on what I want to achieve (with high gpu load games I usually prefer traditional vsync and no tearing)

As long as I put a value in RTSS Scanline Sync box (not 0) what I get is:
vsync on ingame -> traditional vsync
vsync off ingame -> scanline sync (no tearing as long as the GPU can keep up, 60fps)

Just to be clear, with RTSS Scanline Sync box at 0:
vsync on ingame -> traditional vsync
vsync off ingame -> no vsync (tearing, uncapped framerate)

In the end, that's why I don't use individual game profiles, I usually set vsync ingame according to my needs.

[I have "framerate limit" at 0]

 

[EeK9X]

Great one stop guide to use Scanline Sync!

But requires a lot of effort to set this up with hard prerequisites for the Scanline Sync to work properly, a point which is reached to an approximate level with FPS set very close and slightly lower than the monitor's actually refresh rate in decimals before enabling Vsync.

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Indeed, that's the other low lag/no tearing/Vsync off method that I mentioned (and explain in detail here). It was my go-to solution until very recently, when I started noticing improvements in how Scanline Sync worked. As I said, I'll probably add it to a threadmark in a future update.

It requires a lot less effort, but since it's not entirely lag-free (it introduces up to one frame of delay), if you can get Scanline Sync to work, the latter is unbeatable - except when put against G-Sync/FreeSync, of course. Still, even RTSS's fps limiter is much better than the alternatives.

Thanks for your reply.

I'd like to point out that I'm not 100% sure disabling vsync at driver level is required.
I mean, vsync HAS to be off for scanline to work, but that can be done using game settings in my testings. I haven't notice a difference disabling it at driver level too.

I have both nvidia (2080ti) and amd (Vega56), and I use the default driver setting (=let the game decide)

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Ah, yes, you're right about not necessarily having to turn off Vsync at the driver level if the default setting ("Use the 3D application setting", for Nvidia GPUs) is enabled.

My advice was aimed towards users who set vertical sync to either "On" or "Adaptive" (globally or for each game, individually). That would override all in-game settings and cause issues with Scanline Sync.

I thought it was better to recommend setting Vsync to "Off" as a general rule of thumb, than to have people running into problems due to a setting that is easily overlooked. But I made that even more clear in the FAQ. :)

 

[BeI]

Fingers crossed for one day seeing RTSS + scan line sync integrated into Steam, alongside the existing controller support. Would be so nice to be able to just go into the Steam overlay and pick a per-game fps cap and tick a box for scan line sync, or something like that.

 

[trioptimum24601]

Can't get the hotkeys entry in the global config file to work... I have the OSD up with the sync information, but holding Ctrl+Shift and hitting the up and down keys doesn't make any change to the visible position of the tear, nor the value for Sync Line 0. Might have to try making adjustments first and then launching games to check.

 

[Shocchiz]

Can't get the hotkeys entry in the global config file to work... I have the OSD up with the sync information, but holding Ctrl+Shift and hitting the up and down keys doesn't make any change to the visible position of the tear, nor the value for Sync Line 0. Might have to try making adjustments first and then launching games to check.

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I had the same problem (and others) with RTSS beta 3, but beta 2 is fine (the one included in latest Afterburner).

 

[GReeeeN]

Not sure if ive gotten it to work as the Cntrl + Shift and arrow up and down were not working, so I just applied a global setting of -140 in scanline sync at 4k.

So while I do not see any tearlines which is great with this global setting of -140, the whole exerpeine is just very "jittery" compared to Vsync ON. A slow pan results in everything just not being smooth at all, something kind of like microstutter. Am I doing something wrong?, My fps is at around 85-90 which is well above the 60hz limit on my TV, but the game just isnt smooth and looks bad to be honest. .

Am I doing somethign wrong?, Is this normal?, or am I just use to Vsync ON smoothness?

Is Scanline Sync meant to lock FPS to the refresh rate?, because again following all the steps above and entering -140 in the Scanline sync box, my fps in game is showing 85-90.

EDIT: relaunching everything managed to get the hotkeys to work, but the overall experience is still very jittery when compared to Vsync ON and FPS has not auto locked to refresh rate as others have mentioned it should?

 

[EeK9X]

EDIT: relaunching everything managed to get the hotkeys to work, but the overall experience is still very jittery when compared to Vsync ON and FPS has not auto locked to refresh rate as others have mentioned it should?

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If Scanline Sync were working as intended, your frame rate should cap out at 60, since it essentially limits your fps to try to match it to your display's refresh rate.

An unlocked frame rate means that you're on the right path, but RTSS itself isn't properly configured.

Go through the tutorial again and make sure that your CFG files aren't missing anything (especially since the OP has been updated with extra tips).

 

[GReeeeN]

If Scanline Sync were working as intended, your frame rate should cap out at 60, since it essentially limits your fps to try to match it to your display's refresh rate.

An unlocked frame rate means that you're on the right path, but RTSS itself isn't properly configured.

Go through the tutorial again and make sure that your CFG files aren't missing anything (especially since the OP has been updated with extra tips).

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are there any known issues with Scanline Sync on multiple monitors?, im trying to play on my TV (60hz) while having a 120hz monitor also connected.

I've followed the steps exactly again and still getting uncapped frame rate on my tv/60hz.


EDIT: so after some playing around, it does appear multiple monitors does actually throw Scanline Sync right off from locking FPS properly. It appears RTTS uses the primary PC display when Scanline Sync tries to lock fps to the monitors refresh rate.

A few things I tried included:

1. Setting the TV as the primary monitor without a reset - didn't work (it still used the 120hz pc monitor as the source)
2. Setting all monitors to 60hz - which did lock Scanline Sync to 60fps, but with a lot of stutter (I'm assuming it still read the primary PC monitor as the source and locked it to that 60hz and not the TVs (not all 60hz are the same aka 59.90, 59,70, etc)

The only way I managed to get it working was to disable my primary monitor in NVCP, followed by resetting windows to "force" the TV to be the only display. Once this was done, it seemed RTSS finally managed to pickup the TV Hz as the main source and locked the fps properly with no stutters.

While it was a fantastic experience, it appears to be a bit of a lengthy process for those with multi-monitor displays. Is there any work around to this?, or any line we can add to the config file in RTSS to select which monitor Scanline Sync should read off without disabling monitors and resetting windows?

Manually disabling the primary PC monitor and resetting the system every time I want to use Scanline Sync on TV, and then turning the PC Monitor back on in NVCP and resetting the system again seems to be a bit of a long and manual process.

thanks

 

[Deleted member 30124]

.

 

[EeK9X]

are there any known issues with Scanline Sync on multiple monitors?, im trying to play on my TV (60hz) while having a 120hz monitor also connected.

I've followed the steps exactly again and still getting uncapped frame rate on my tv/60hz.


EDIT: so after some playing around, it does appear multiple monitors does actually throw Scanline Sync right off from locking FPS properly. It appears RTTS uses the primary PC display when Scanline Sync tries to lock fps to the monitors refresh rate.

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Ah, yes. You didn't mention that you were using multiple displays before. There's a setting that you can add to your Global profile to make RTSS sync to the appropriate display:

1. Open the Global CFG file using Notepad;
2. Under "[Framerate]", add "SyncDisplay=X", where "X" is the number of the desired display.

Note: The default is "0" (only one monitor); On a dual monitor setup, try setting it to "1", instead.

I didn't even think of including it in the guide, since I only run one display myself. Let me know if that works so that I can update the guide!

Also, when changing graphical settings, editing EDIDs, etc., try simply restarting the graphics driver (Win+Ctrl+Shift+B) instead of going through the entire reboot process.

 

[GReeeeN]

Ah, yes. You didn't mention that you were using multiple displays before. There's a setting that you can add to your Global profile to make RTSS sync to the appropriate display:

1. Open the Global CFG file using Notepad;
2. Under "[Framerate]", add "SyncDisplay=X", where "X" is the number of the desired display.

Note: The default is "0" (only one monitor); On a dual monitor setup, try setting it to "1", instead.

I didn't even think of including it in the guide, since I only run one display myself. Let me know if that works so that I can update the guide!

Also, when changing graphical settings, editing EDIDs, etc., try simply restarting the graphics driver (Win+Ctrl+Shift+B) instead of going through the entire reboot process.

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Perfect thank you!, I will give this a shot. As I have 3 monitor setup I'll try "2" and report back.

 

[EeK9X]

Perfect thank you!, I will give this a shot. As I have 3 monitor setup I'll try "3" and report back.

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It should be "2", from what I understand, as the monitor index is "zero based", according to Unwinder. So, it starts with "0".

Please do report back and let me know what works!

 

[GReeeeN]

It should be "2", from what I understand, as the monitor index is "zero based", according to Unwinder. So, it starts with "0".

Please do report back and let me know what works!

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Yep it was "2" that worked and locked it to the 3rd monitor. Now I can have Scanline Sync running per game, per monitor running. Thank you!

 

[oneils]

I've been looking for a guide like this. A lot of the guides do not explain how to edit the global configuration file. They assume that you know how to do it. Thanks for this. I'm going to try this out for my build that is connected to a TV.

 

[Ruranghi]

Great guide mate, thanks for this.

Had a quick question: I'm capping a bunch of my games to half my refresh rate (30hz) using 1/2 scanline sync and its working really well so far, I've hidden the tear line effectively in Abzu, Hitman 3 and Resident Evil 2 Remake. The input lag is great and frame-pacing is great, but I have some very small problems.

In Abzu at certain really specific locations I get a rolling tear as I pan the camera even though GPU usage is still below 60%, is there anyway to know why thats happening? In Hitman 3 the usage goes to 80% but I don't get this problem, RE2R has spikes of extreme GPU usage in certain cutscenes and I get a tear there but that makes sense to me since I'm saturating the GPU completely.

I tried using fast sync + scanline-sync but that just gave me loads of microstutters, although I didn't try setting the scanline index to 1 (I'm at -140 when not using any V-Sync wth the Scanline-Sync) Other guides recommended doing this but I didn't really understand the explanation they gave.

Generally GPU usage is around 40-50% at 30hz in Abzu so really I should be able to do 60hz but certain scenes have a 50% delta and I really want those scenes to run without stutter/tearing. The game has unexplained stutters for me when I use normal v-sync and try to play at 60hz at 1620p even though my GPU usage never exceeds 80%, so its possibly just problems with the game itself but I wanted to be sure its not scanline sync related.

Sorry for writing out a screed, the TL;DR is: Why would a game tear when I've hidden the tear line and I'm nowhere near maxed out GPU usage, do I effectively need 50% usage and below to eliminate all tearing? Or will this method of syncing still not stop these kinds stutters?

 

[EeK9X]

I've been looking for a guide like this. A lot of the guides do not explain how to edit the global configuration file. They assume that you know how to do it. Thanks for this. I'm going to try this out for my build that is connected to a TV.

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You're welcome, hope it worked out well!

Great guide mate, thanks for this.

Had a quick question: I'm capping a bunch of my games to half my refresh rate (30hz) using 1/2 scanline sync and its working really well so far, I've hidden the tear line effectively in Abzu, Hitman 3 and Resident Evil 2 Remake. The input lag is great and frame-pacing is great, but I have some very small problems.

In Abzu at certain really specific locations I get a rolling tear as I pan the camera even though GPU usage is still below 60%, is there anyway to know why thats happening? In Hitman 3 the usage goes to 80% but I don't get this problem, RE2R has spikes of extreme GPU usage in certain cutscenes and I get a tear there but that makes sense to me since I'm saturating the GPU completely.

I tried using fast sync + scanline-sync but that just gave me loads of microstutters, although I didn't try setting the scanline index to 1 (I'm at -140 when not using any V-Sync wth the Scanline-Sync) Other guides recommended doing this but I didn't really understand the explanation they gave.

Generally GPU usage is around 40-50% at 30hz in Abzu so really I should be able to do 60hz but certain scenes have a 50% delta and I really want those scenes to run without stutter/tearing. The game has unexplained stutters for me when I use normal v-sync and try to play at 60hz at 1620p even though my GPU usage never exceeds 80%, so its possibly just problems with the game itself but I wanted to be sure its not scanline sync related.

Sorry for writing out a screed, the TL;DR is: Why would a game tear when I've hidden the tear line and I'm nowhere near maxed out GPU usage, do I effectively need 50% usage and below to eliminate all tearing? Or will this method of syncing still not stop these kinds stutters?

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No problem! Regarding your issue, there are a few points to consider:

1. You mentioned that you're capping your games to half of your display's refresh rate. Assuming you have an Nvidia GPU, that means you're probably enabling "Adaptive Vsync (half refresh rate)" on the Nvidia Control Panel. When using Scanline Sync, you want neither of those things (see FAQ items 5.2 and 5.3). For best results, you need an uncapped frame rate and Vsync disabled, both in-game and at the driver level;

2. Most Unreal Engine 4 games, such as Abzû, suffer from poor asset streaming, meaning that when transitioning between portions of a level, you experience hitches or stutters. There's no way around that, unfortunately, as the same behavior occurs even on ultra fast NVMe SSDs. To know for sure if what you're seeing is related to the game's engine or something else, I'd recommend enabling regular Vsync (not Adaptive), either in-game or at the driver level, and then replaying the same areas where you noticed the odd behavior (remember that variations in frame time, perceived as stuttering, will more than likely result in a tear line when using S-Sync). If it stutters with Vsync on, it's the game's fault;

3. Lastly, when properly configuring S-Sync (uncapped frame rate and Vsync off), try experimenting with Fast Sync - either combined with S-Sync (see items 1.2 and 4.2), or by itself, in conjunction with an FPS cap of 2-3 frames above your display's maximum refresh rate, as I explain here. Usually, when the results with S-Sync aren't satisfactory, and VRR isn't an option, I tend to go with that alternative.

Let me know how it goes, good luck!