Stutter Stutter or Smooth as Butter

[jimortality]

Brands Hatch especially, even in practice screen stutter. I think it's not just me and maybe down to the unreal engine? I've tried all different things so if you're smooth as Butter, please post your settings and how you're eliminating it. Thank you.

Acer Predator X34p
I 7-6700k
Nvidia 1080ti
16gb Ram a lam.
And not forgetting my brand new Master Cooler 212 Evo

 

[Case_]

Probably because your PC isn't able to deliver 144 Hz and reaches its limits while trying so. Be it CPU or GPU limit.

 

[Bomberos_]

it would make sense, but: i have also other games running with just 50 to 60 fps and there is no stuttering while my monitor is set on 144 Hz

 

[Case_]

And what is your CPU and GPU usage in those games compared to ACC?

 

[Bomberos_]

same like in ACC, it's never more than 80% CPU and GPU usage.
i guess there is another ...maybe game engine... reason, why this happens only in ACC.

 

[Case_]

Overall CPU usage doesn't tell you much, you must look at the actual thread usage (using Process Explorer, for example). You can be completely CPU bottlenecked with overall CPU usage below 10%. (But it's more than likely you are indeed CPU bottlenecked with CPU usage being so high.)

 

[DrRob]

After having a chat with @RasmusP about maybe activating G-sync on my setup although the monitor is not listed as compatible, I managed to establish a compromise I can very well live with!

First of all thank you again Rasmus for taking your time to explain the details, much appreciated!

What I have now is a GTX1070 running stable G-Sync on a Samsung 1080p UW 49" Freesync2 in ultimate mode. FPS cap in game at 55 FPS.

Funnily enough the ultimate mode was supposed to be the less preferred, as reserved for Freesync only, but that surprisingly worked the best for me. The only artifact I am getting is a slight brightness modulation as soon as the G-sync logic switches from single frames to doubled frames (I cannot give an exact technical explanation I am afraid).
Therefore I have the FPS cap to mostly keep the FPS in only one frame mode to prevent the jump in brightness. I still get the occasional one and I may have to adapt that FPS cap from track to track, I will have to see.

I believe "G-Sync compatible" requires to go much more down in possible FPS range in sync'ed mode than my monitor can handle, hence no certificate for G-Sync. I'd have to look again at the specifics. On top of my head the ultimate mode offers a wider range than the standard mode and that may be the reason I got it running in that mode although other sources suggest standard mode.

Overall: Happy bunny!

 

[RasmusP]

After having a chat with @RasmusP about maybe activating G-sync on my setup although the monitor is not listed as compatible, I managed to establish a compromise I can very well live with!

First of all thank you again Rasmus for taking your time to explain the details, much appreciated!

What I have now is a GTX1070 running stable G-Sync on a Samsung 1080p UW 49" Freesync2 in ultimate mode. FPS cap in game at 55 FPS.

Funnily enough the ultimate mode was supposed to be the less preferred, as reserved for Freesync only, but that surprisingly worked the best for me. The only artifact I am getting is a slight brightness modulation as soon as the G-sync logic switches from single frames to doubled frames (I cannot give an exact technical explanation I am afraid).
Therefore I have the FPS cap to mostly keep the FPS in only one frame mode to prevent the jump in brightness. I still get the occasional one and I may have to adapt that FPS cap from track to track, I will have to see.

I believe "G-Sync compatible" requires to go much more down in possible FPS range in sync'ed mode than my monitor can handle, hence no certificate for G-Sync. I'd have to look again at the specifics. On top of my head the ultimate mode offers a wider range than the standard mode and that may be the reason I got it running in that mode although other sources suggest standard mode.

Overall: Happy bunny!

Awesome mate!

I now have gsync since 1.5 years and I have to say it's massively reducing the stress to configure everything to have no microstuttering or input lag due to vsync and frame spikes.
Just set the fps limiter to wherever the framerates becomes stable and that's it. Everything above 40 fps is "smooth enough to play". For racing 80 fps or more are awesome though, ofc.

Now with gsync compatible mode I can only recommend to get a nice monitor that suits all your needs and is compatible. Or just get an AMD card. It's just awesome.

Money well spent if you're sensitive to stuttering (i.e. can't enjoy fluctuating fps without any sync on your 144 hz monitor. For me no sync is always stuttering).

 

[DrRob]

@RasmusP
For sure I will put more focus on G-Sync compatibility for the next monitor (maybe Samsung Odyssey G9?).
I don't see me buying an AMD card at the moment, but we'll see how the next generation of cards will be like.

Forgot to say that now even replays are really enjoyable to watch, since the FPS drop in those is more prevalent than in actual gaming.

 

[DrRob]

Well...I was shooting too early here....

...after seeing Mr.Latte's thread about the new Samsung monitors and today's release of the G9 the previously circulated G-Sync feature turns out to be only a G-Sync compatibility. And what is worse, that the frequency range this works is only 60 Hz upwards, whereas other monitors support 48 Hz upwards.
Underwhelmed to say at least. This means I have to have minium 60 FPS for G-Sync to work.

 

[RasmusP]

Well...I was shooting too early here....

...after seeing Mr.Latte's thread about the new Samsung monitors and today's release of the G9 the previously circulated G-Sync feature turns out to be only a G-Sync compatibility. And what is worse, that the frequency range this works is only 60 Hz upwards, whereas other monitors support 48 Hz upwards.
Underwhelmed to say at least. This means I have to have minium 60 FPS for G-Sync to work.

If it's officially listed as gsync compatible, it should work well with lower fps though, via frame doubling without brightness differences.
But yeah let's see how it turns out from tests before getting hyped...

 

[Alex Townsend]

My monitors aren't listed officially. I have three AOC g2790px monitors, it's strange as the little brother, the g2590px, is listed as g-sync compatible and is the same monitor just smaller.
Is there some other list that is more up to date? The nVidia page doesn't look like it's been updated in a long time...

Regardless, I have mine running in g-sync compatible mode just fine. Silky smooth on pretty much everything, with some settings turned down as triples take their toll on most titles.

I didn't know about the minimum required fps for g-sync compatible to work, it would appear I'm ok as ACC never drops below 70fps with the settings I've made using a 2070s.
I am waiting for the new 3000 cards to arrive so I can turn the graphics up a bit more though.

 

[RasmusP]

My monitors aren't listed officially. I have three AOC g2790px monitors, it's strange as the little brother, the g2590px, is listed as g-sync compatible and is the same monitor just smaller.
Is there some other list that is more up to date? The nVidia page doesn't look like it's been updated in a long time...

Regardless, I have mine running in g-sync compatible mode just fine. Silky smooth on pretty much everything, with some settings turned down as triples take their toll on most titles.

I didn't know about the minimum required fps for g-sync compatible to work, it would appear I'm ok as ACC never drops below 70fps with the settings I've made using a 2070s.
I am waiting for the new 3000 cards to arrive so I can turn the graphics up a bit more though.

Nice to hear!

There are some community lists:

Unofficial list of Nvidia G-Sync compatible Freesync monitors tested by the community | Esports Tales

This list contains hundreds of Nvidia G-Sync compatible monitors tested by the community. Find out the Freesync displays that can be enabled without problems.

www.esportstales.com

And a massive list on the German pcgh website:

Sammelthread - User melden Gsync Kompatibel - Monitorliste

Hallo zusammen. Da es ja nun sehr viele Monitore gibt die trotz "nein" von Nvidia scheinbar doch mit Gsync-Compatible funktionieren, wollte ich hier einen Thread aufmachen um eure Erfahrungen zu Sammeln. Bitte schreibt in den Thread: Hersteller // Modell // FreeSync Range und was euch...

extreme.pcgameshardware.de

 

[Alex Townsend]

Nice to hear!

There are some community lists:

Unofficial list of Nvidia G-Sync compatible Freesync monitors tested by the community | Esports Tales

This list contains hundreds of Nvidia G-Sync compatible monitors tested by the community. Find out the Freesync displays that can be enabled without problems.

www.esportstales.com

And a massive list on the German pcgh website:

Sammelthread - User melden Gsync Kompatibel - Monitorliste

Hallo zusammen. Da es ja nun sehr viele Monitore gibt die trotz "nein" von Nvidia scheinbar doch mit Gsync-Compatible funktionieren, wollte ich hier einen Thread aufmachen um eure Erfahrungen zu Sammeln. Bitte schreibt in den Thread: Hersteller // Modell // FreeSync Range und was euch...

extreme.pcgameshardware.de

Good to know it is on a list as working and I wasn't going completely mad... lol

Strange that flickering on the g2590 is ok and its listed as compatible yet no flickering for me on the larger version and it's not officially listed... hmmm

Ghosting though, I have had that sporadically in ACC. All I do is switch the offending monitor, (as it's usually on 1 or 2 out of the 3), to another input and then it switches back automatically and the ghosting is gone. It's completely random though which is a bit annoying.

 

[RasmusP]

Btw guys, the creator of the Nvidia inspector (Orbmu2k) created another neat piece of code:

A vblank display for the rtss osd. So no need for the hz display from the gsync (and some freesync) monitor or having the gsync indicator on to make sure gsync is working.

Both are pretty big and at fixed positions so this vblank display is very nice, just adds another little number into the rtss osd.

Link (in German though but you should be able to find the download):

3DCenter Forum - [Tool] RTSS - NVIDIA VBlank Status (GSYNC Indicator)

[Tool] RTSS - NVIDIA VBlank Status (GSYNC Indicator) nVidia Grafikkarten

www.forum-3dcenter.org

 

[Noctam]

Thanks a lot guys for sharing your experiments, it's super interesting for neophytes like me!

How would you set a computer for best performance but also no tweaking between screen sessions and VR sessions?
I'm setting up a rig for my dad and I'm trying to make it as smooth and easy as possible for him.

 

[RasmusP]

Thanks a lot guys for sharing your experiments, it's super interesting for neophytes like me!

How would you set a computer for best performance but also no tweaking between screen sessions and VR sessions?
I'm setting up a rig for my dad and I'm trying to make it as smooth and easy as possible for him.

Depends on the VR headset and the monitor!
Especially on the refresh rate of each and the resolution.

With a gsync/freesync monitor that has 100 Hz or more and a standard VR headset that has the classic 90 Hz, I would limit the fps at 91 fps to make it smooth for both.
You could set rtss (riva tuner) to a global limit, so every game (but also every video card using application like excel, power point, video editing software).

Then you would simply configure the graphic settings to run fine in VR and then do a quick test if it's also running fine on the monitor. If you have a oculus rift vs 4k triple monitors, the 4k triple monitors will need a way faster graphics card than the oculus rift.
If you have a single 1920x1080 monitor vs the HP Reverb with 4320x2160 pixels, the VR headset is way more heavy for the graphics card.

If it's a monitor without variable refresh rate, then I'd suggest either buying one or buying a monitor with 144 hz. At 144 hz, the stuttering won't be that noticeable, no matter the fps.

If it's a standard 60 Hz monitor, we have some problems...
You'd need to force vsync and limit the fps via rtss to -0,01 fps below the accurate hz value (find out via vsynctester). But that limit will be too low for VR headsets...

So you could choose between input lag or tearing/stuttering on the monitor or having stuttering in the VR headset.
Both are awful!

 

[Noctam]

Thanks a lot for your answer RasmusP!

I would limit the fps at 91 fps to make it smooth for both. You could set rtss (riva tuner) to a global limit, so every game.

What impact would this have for games that are not running at such high fps though?

For my dad I bought a Freesync 75Hz monitor and a Quest 2 (although we're waiting for a better gpu to really exploit the later).

So if I understand you right, you need to set a limiter 1FPS higher than the headset refresh rate? Do you know why?
In my case it's tricky because the headset is at 90hz but the screen despite being freesync is at 75hz only so what would be the lesser evil?
Setting the limit it at 91fps and running vsync off for the monitor or Vsync on with no limit?

Then you would simply configure the graphic settings to run fine in VR and then do a quick test if it's also running fine on the monitor.

Can't I set different settings for VR and monitor modes?

At 144 hz, the stuttering won't be that noticeable, no matter the fps.

I'm not sure I understand, why would the stuttering not be noticeable with a non variable refresh rate monitor at 144Hz? If I only reach 60fps for example, why would the screen behave differently than a 60Hz one here?

Sorry, I have so many questions about this!

 

[RasmusP]

What impact would this have for games that are not running at such high fps though?

For my dad I bought a Freesync 75Hz monitor and a Quest 2 (although we're waiting for a better gpu to really exploit the later).

So if I understand you right, you need to set a limiter 1FPS higher than the headset refresh rate? Do you know why?
In my case it's tricky because the headset is at 90hz but the screen despite being freesync is at 75hz only so should I just set the limit it at 91fps nonetheless and run vsync off for the monitor? Or everything Vsync with no limit?

This is a bit more complicated but basically:
For freesync/gsync monitors you need the limiter to be set at least 3 fps below the maximum Hz. But you can set the limiter lower if you want. It just needs to be within the freesync/gsync range. Not sure what's the range of that monitor, most 75 Hz monitors tend to be only "freesync" from 50-75 Hz for example.
3 fps because all limiters have fluctuations and you don't want the fps to fluctuate over 75 fps. That would either cause tearing (no vsync) or input lag (vsync).

But you need the limiter to be ABOVE the Hz of the VR headset. VR headsets always use vsync (afaik it's forced, you can't set anything there! But it's very low input lag.. I never fully read into this topic...).
So if you'd limit below the Hz of the headset, it would drop to half of it. So 45 fps with inserted, artificial images in between to have "90 fps" for the always 90 Hz.
Oculus Rift calls this "asw".

That's why I suggested 91 fps. Most headsets run at 90 Hz so the limiter won't interfer with the headset. Most monitors have 100 Hz or more. So the limiter would be low enough for all these monitors.

Can't I set different settings for VR and monitor modes?

Sadly not. In-Game limiters don't make a difference between VR or monitor, riva tuner doesn't make a difference and I'm not sure about the graphics card's limiters, but I don't think they have such an option...

I'm not sure I understand, why would the stuttering not be noticeable with a non variable refresh rate monitor at 144Hz? If I only reach 60fps for example, why would the screen behave differently than a 60Hz one here?

Sorry, I have so many questions about this!

When you draw it on a paper. 144 pieces per second above 60 pieces per second, you'll see for how long a tearing border would be visible. It's very short.
The ratio is 2.4.
Dropping down to the lowest "round number", this would mean:
12x refreshing the monitor
5x new frame
(144 to 60).
Or in ms: 6,94ms refresh cycle, 16.67ms fps cycle.

Or from another perspective:
Without any sync, the new frame from the GPU will just be inserted to the refresh cycle of the monitor. The monitor refreshes from top to bottom and at 144 Hz, this takes 6,94ms to complete.
Due to no sync in my drawing, you will have about:
1. tear: 4ms
2. tear: 2ms
3. tear: 4ms
4. tear: 3.5ms
The tearing border will be visible during my "filled out" areas.

Very not mathematical but it really shows what's happening!
With vsync, the new frame from the GPU would be held back until the next refresh cycle. The issue there would the input lag from this but also an irregular pattern:
First frame would be displayed for 3 refresh cycles, the second frame would only be displayed for 2 refresh cycles!
The 3rd frame would be displayed for 3 cycles and the 4th frame again for 2 cycles.

You would definitely see the stuttering...

But would you spot the tearing boarder that crawls down on the monitor from top to bottom for only 2-4ms? I didn't... It doesn't look like "tearing". More like some glitching on some objects where you would spot it.

With freesync/gsync however, the monitor would go to either:
120 Hz and show each frame 2x
60 Hz and show each frame 1x

And to close on this:
If you take a 60 Hz monitor and limit the fps at 60 and don't use any sync, you might end up with this:

Correction:
In this case the tearing border would be close to the top of the monitor and be always in the same place.
But most of the times, monitors (or limiters) are not perfect so the tearing border would slowly crawl to the top or the bottom. Each refresh cycle a little bit...

When you have fluctuating fps, the tearing border will move around on the monitor.

 

[RasmusP]

Putting this into another post:

One solution might be to put the "low latency setting" in the nvidia driver settings to "ultra". I'd have to read about it again but as far as I remember, this automatically puts on vsync AND sets an fps limit!
And also as far as I know, this setting will be ignored for VR headsets, since they don't use vsync, pre-rendered frames or anything.

BlurBusters about the ultra setting:
" When combined with G-SYNC + V-SYNC, this setting will automatically limit the framerate (in supported games) to ~59 FPS @60Hz, ~97 FPS @100Hz, ~116 FPS @120Hz, ~138 FPS @144Hz, ~224 FPS @240Hz, etc. "

What graphics card will that PC be running on btw? AMD or nvidia?

And here's a video from myself:
240 fps camera, recording 60 fps on my "60 hz" monitor. The real hz according to vsynctester is 58.84 Hz, so you'll see the tearing border slowly crawling across the monitor. My monitor also refreshes from bottom to top.
If I'd set the fps limit to 58.84, the tearing border would stand still somewhere on the screen. Depending on how asynchronous the scan out process started at the first frame

 

[Case_]

(Yeah, on a 75 Hz monitor, Freesync range will almost certainly be 48-75 Hz. )