Input lag

[Atom1kk]

Hi. I had this issue since years but never bothered, but now i want to find the reason for this input lag.

When I turn my wheel on the monitor there is a very small delay, but it is not in all games. in Assetto Corsa everything is fine, even with the fastest movements. But than in Raceroom this effect is very clearly seen on fast movements.

I have an standard WQHD 27" monitor with 60 Hz.

is it becoause of the low Hz? but than this effect would be in all games i think.

THX

 

[5-Card-Major]

Good article covering this, i.e. higher fixed refresh rate and Variable refresh rate scenarios

Factors Affecting PC Monitor Responsiveness | PC Monitors

A detailed look at factors such as input lag, pixel response time and our perception and how this affects the responsiveness of a monitor.

pcmonitors.info

This one explains Input lag in more details

Exploring Input Lag Inside and Out

www.anandtech.com

I like this site as well for monitor reviews and info.

High Refresh Rate Panels and Displays - A Road-map and Round-up - TFTCentral

Looking in detail at all the available and planned high refresh rate panels, and monitors available in the market

www.tftcentral.co.uk

 

[Atom1kk]

ok tried the option with low latency mode and it was a little bit better. Spoke today with my friend and he gave me a really good hint. he said that I should set my FPS to max 59. and this really did the job.

 

[Spinelli]

FreeSync associated I believe w/ AMD , GSync w/nVidia, so depends what you have...this feature of a graphics card helps reduce motion blurr.

They're made to get rid of stuttering and tearing associated with the game's fps not being in sync with the monitor's refresh rate - nothing to do wth reducing motion burr. It may also have some added benefit of helping a touch with motion blur but, if so, that's just a bonus (plus, motion blurr would still be bad due to LCD's using sample-and-hold tech unless using the monitor in strobing mode AKA "blurr reduction mode", "Lightboost", "Ultra Low Motion Blurr"). I believe there's finally a monitor that can do strobing and G-Sync/FreeSync at the same time; I think it's those 2 fairly new Gigabyte Aorus models. Pretty sure no other monitiors can do both simultaneously yet.

The higher the refresh rate monitor the the less noticeable impact from VSync, considering you can maintain that FPS. Frametime is lower and this is what causing VSync lag, it has to wait for the next sync to flush the buffer.

All monitors have different input lag and it goes way beyond frametimes. You can have a game running at 400 fps and still have lots of input lag. A large portion of input lag can come from other aspects of the monitor's hardware, software processing, etc. regardless of the monitor's refresh rate and the game's framerate. You can have 2 different monitors running the exact same refresh rate while displaying the exact same game at the exact same fps and have much more/less input lag on one monitor compared to the other.

ok tried the option with low latency mode and it was a little bit better. Spoke today with my friend and he gave me a really good hint. he said that I should set my FPS to max 59. and this really did the job.

Use MSI Afterburner to set the max framerate it's the next best thing from using a game's in-built max framerate option (not all games have it). Also, MSI Afterburner has the scanline setting which allows you to move the screen-tearing so it's almost not visible or completely not visible which can potentially improve a user's non-vsync experience.

It goes something like this. In-game framerate option (built right into the game's coding) generally offers the lowest input lag. Next best thing is to use MSI Afterburner. Having said that, MSI Afterburner is generally the most consistent (less framerate variations like 58.7, 59.8, 59.3, etc.).

 

[5-Card-Major]

Funny, I sometimes write about these things, yet when I play I don't even notice it, and it doesn't bother me.

 

[Deleted member 197115]

All monitors have different input lag and it goes way beyond frametimes. You can have a game running at 400 fps and still have lots of input lag. A large portion of input lag can come from other aspects of the monitor's hardware, software processing, etc. regardless of the monitor's refresh rate and the game's framerate. You can have 2 different monitors running the exact same refresh rate while displaying the exact same game at the exact same fps and have much more/less input lag on one monitor compared to the other.

Guess VSync in my post did not register.

Also NVidia supports max framerate in control panel now.

 

[Spinelli]

Yup. I read that MSI Afterburner's max framerate option is better than Nvidia's. I can't remember if it was better in terms of less input lag (apparently, setting a max framerate adds tiny amounts of input lag, this is why game's own in-built limiters tend to have the least input lag) or of it's better in terms of framerate consistency but it's generally supposed to be better.

I'm very picky about input lag but, I have to admit, I've never noticed input lag from using max framerate limiter so I've never noticed any of this myself; I'm just passing along what I learned/read about from some hardcore input lag sites/threads.

I'll find some links later.

I recommend MSI's Afterburner anyways as, besides the max framerate control, it has the "scanline sybc" feature which is big for anyone not using GSync / Freesync

From a user using the "scanline sync" feature (different from the regular framerate limiter feature):
"It works very well in my opinion - in fact it's awesome. I can't say it adds any significant amount of lag, and after playing for many years with no VSync at all I can't believe how nice and smooth the image is."

RTSS Scanline Sync HOWTO - Blur Busters Forums

 

[Deleted member 197115]

Never understood all these exotic methods and why people go through that trouble. It's either you are indeed hyper sensitive or have bad monitor or some other bottleneck in you system dragging the rest down.
Myself never had any issues with VSync and one frame flip queue and not only in sims but use the same setup in FPS games. I just don't see that lag, crosshair follows the mouse as quickly as I twitch it.
May be I am just lucky or my reflexes are way slower than Vsync to perceive that lag.
Although based on this paper average male reaction time is 220ms and threshold when lag is subjectively getting noticeable is around 100ms.
Frametime for 60Hz monitor is only 16.7ms, VSync worst case scenario can what, double it?
But as Spinelli mentioned and linked article explains, GPU to monitor is just a small portion of the total input lag and different components in the system as well as game itself contribute the rest. That last phase can just push it over the hill when you start seeing it.

 

[Fabione71]

For RaceRoom check if the wheel rotation animation is locked at 180°.

 

[Neilski]

Never understood all these exotic methods and why people go through that trouble. It's either you are indeed hyper sensitive or have bad monitor or some other bottleneck in you system dragging the rest down.
Myself never had any issues with VSync and one frame flip queue and not only in sims but use the same setup in FPS games. I just don't see that lag, crosshair follows the mouse as quickly as I twitch it.
May be I am just lucky or my reflexes are way slower than Vsync to perceive that lag.
Although based on this paper average male reaction time is 220ms and threshold when lag is subjectively getting noticeable is around 100ms.
Frametime for 60Hz monitor is only 16.7ms, VSync worst case scenario can what, double it?
But as Spinelli mentioned and linked article explains, GPU to monitor is just a small portion of the total input lag and different components in the system as well as game itself contribute the rest. That last phase can just push it over the hill when you start seeing it.

I thought the same as you - that the lag on my 60 Hz display (with vsync on) would be a non-issue, maybe 2 or 3 frames worth, tops.
Then I measured it in AC and found that it was 90 ms...
I changed a few settings (some info here) and got it down to roughly what I had originally expected it to be (LOL), and I'm pretty certain it made a big improvement to my car control.

 

[Deleted member 197115]

I thought the same as you - that the lag on my 60 Hz display (with vsync on) would be a non-issue, maybe 2 or 3 frames worth, tops.
Then I measured it in AC and found that it was 90 ms...
I changed a few settings (some info here) and got it down to roughly what I had originally expected it to be (LOL), and I'm pretty certain it made a big improvement to my car control.

Pretty much same findings as mine, MAXIMUM_FRAME_LATENCY=1, which is the same as Nvidia Low Latency Mode On, gives nice improvement even with VSync.
Vsync off is still the best, but how many can swallow jittery picture without it.

EDIT: Oh, just noticed it was ACC not AC, man that thing is horrible.

 

[Neilski]

EDIT: Oh, just noticed it was ACC not AC, man that thing is horrible.

Yeah, I guess I confused people by posting my AC measurements to an ACC thread...
I still can't quite believe how bad Martin's lag is in ACC. I am gonna measure my own ACC lag when I get a moment...

 

[Case_]

Vsync off is still the best, but how many can swallow jittery picture without it.

And that is exactly why people go through all the trouble with the exotic methods like scanline sync

 

[Deleted member 197115]

And that is exactly why people go through all the trouble with the exotic methods like scanline sync

And I bet it's just as smooth as VSync.

 

[Case_]

Yes, but with half (or less) the input lag.

 

[Deleted member 197115]

Yes, but with half (or less) the input lag.

I'll take your word for it as I honestly haven't tried it. The official guide states different, but I wasn't digging too much into details. Thanks heaven VR does not need any of that.

Pros/Cons

Full framerate
RTSS + Any sync = Identical look with almost identical lag

Framerate Slowdowns
RTSS + VSYNC OFF = tearlines will reappear
RTSS + Fast Sync / Enhanced Sync / VSYNC ON = stutters will reappear

Choose Your Preference
Some people are more sensitive to stutters.
Some people are more sensitive to tearing.

 

[Case_]

If you mean the "identical look with almost identical lag" bit, then I honestly don't understand what is that supposed to mean.

But note that in the actual guide one post above, he states:

"4. If properly configured, it looks like a lagless version of VSYNC ON. "

Which is exactly the point. It gives you the look of vsync on, but eliminates a lot of the lag.

BTW, I don't know much about VR, but I'd be willing to bet it faces the exact same issues, it's just that they're less noticeable for obvious reasons. You'd likely still benefit from lowering the input lag in VR.

 

[Mr Deap]

You can adjust the FOV so you can't see the steering wheel & everything appear to move slower & delay feeling will disappear.

 

[Case_]

Yep, sticking your head in the sand definitely makes all problems disappear.

(Especially when adjusting FOV of all things.)

 

[Deleted member 197115]

ok tried the option with low latency mode and it was a little bit better. Spoke today with my friend and he gave me a really good hint. he said that I should set my FPS to max 59. and this really did the job.

Any of you guys tried setting Low Latency Mode to Ultra instead of On.
It can help even more.
https://www.howtogeek.com/437761/how-to-enable-ultra-low-latency-mode-for-nvidia-graphics/

Gamescom Game Ready Driver Improves Performance By Up To 23%, And Brings New Ultra-Low Latency, Integer Scaling and Image Sharpening Features

Apex Legends, Battlefield V, Forza Horizon 4, Strange Brigade and World War Z now run even faster, retro and pixel games look better with Integer Scaling, modern games look sharper with NVIDIA Freestyle, and input responsiveness can be improved with our new low latency modes.

www.nvidia.com

 

[Case_]

In my experience, it only introduces microstutter without really having an effect on input lag.