[ppn7]

Hi,

First of all, I would like to thank you for your website and this forum which is full of useful informations !

Then I would like to talk about Freesync/Gsync flickering in general. Particularly the one which is called « brightness flickering »
I found that it is due to variation in refresh rate. And the brightness is not the same at low or high refresh rate. So when I use Gsync/Freesync, if LFC kick in it will jump just for example from 50Hz to 100Hz. Sometimes even if it’s in the range, it will jump to the maximum refresh rate as if Gsync/Freesync was disabled for a second.

I wonder if this brightness variation is valid for all type of monitor ? Does Gsync module manages this issue ? I thought it was only for VA panel but mine is an IPS one.

I thought I could just play without Vsync but finally I can see tearing and Vsync ON without stable frametime is juddering.

So I hope I can find a 1080p/144Hz/IPS without this issue. And I know people won’t necessarily be sensitive to this flickering like I’m not sensitive to interlaced patterns.

Thanks !

[PCM2]

Glad you’re finding it helpful!

The issue with what could broadly be called ‘VRR flickering’ can manifest in various ways. It can be caused by a panel’s sensitivity to the voltage fluctuations that occur when the refresh rate changes, particularly large changes that would occur for example when the LFC boundary is crossed. VA models are usually particularly prone to this. Very occasionally IPS models will have this issue, but it’s rare. G-SYNC modules offer more careful voltage regulation and tighter tuning and will generally eliminate this form of VRR flickering with any panel type. It can also be caused, to a more minor degree in most cases, by slight shifts in gamma as refresh rate changes in a VRR environment. These shifts usually occur for darker to medium-dark shades when significant fluctuations occur and can even be observed on OLED models – for example, this occurs on the Dell Alienware AW3423DW even though it has a G-SYNC module. Most IPS models are free from this sort of VRR flickering as well.

There are a few exceptions and it seems you own one such model. I used to have various issues with ‘G-SYNC Compatible’ on my old GTX 10 series GPU as well, which instantly vanished when upgrading to an RTX 30 series GPU. So this can have an impact in some cases. What are the monitors you’re having issues with and what GPU are you using? Do you see it when running this flickering test, specifically, which shows various grey levels whilst frame rate (and hence refresh rate under VRR) fluctuates significantly? The AOC 24G2(U), for example, sometimes seems to exhibit flickering under VRR, although it seems to vary between units. From the feedback I’ve received on this one it might be something of a combination of both flickering types there. The newer 24G2SP(U) I tested did not exhibit this and I haven’t seen any specific reports that it is affected in this way. It’s something I’ve specifically tested for a while now and will comment on (if it’s there) – and having reviewed a broad range of IPS models I can confidently say that it’s rarely an issue.

[ppn7]

Thank you for the detailed response.

Actually i have the 24G2U v1. I tried the VRR test you provided to me. And I can definitely see the flickerings. I use it with a RTX 3060Ti. In fact i can also see interlace patterns at 60Hz, very less noticeable at >60hz but it doesn’t bother.
I tried the pendulum demo by Nvidia, in the 60-140Hz range, it works well without flickering but as soon as i approach the 48Hz limit, it will spike and flicker.
But in-game i don’t know even the frametime stable it will flicker.

But if i understand, there are monitors that will not flicker even if i get into the LFC ? Like the 24G2SP(U) sample you had tested ? I mean this one had no flickering issue in the VRR test, right ?

I tried a tip provided somewhere in reddit or else where i don’t remember, which is to change CRU range, from 48-144Hz to 72-144Hz for example and capslock to 60fps to stay always into LFC mode, but it doesn’t work properly, it will jump to 144Hz and flicker but less visible since from 120Hz and 144hz brightness will be almost the same.

Let me show you some example it you allow me here :
Gsync range 48-144Hz
Gsync range 72-144Hz
Pendulum Demo – LFC 60 FPS NVCP cap – No flickering
TW3 – LFC 60 FPS NVCP cap – Flickering

Too bad for me that when i bought this monitor 2 years ago, i didn’t have a freesync or gsync compatible GPU to test it. Next time i will for sure check this day one !

[PCM2]

Yeah, it’s definitely that jump from ~60Hz to ~120Hz when LFC kicks in that does it. Or with additional fluctuations that are large enough to set it off (the VRR flickering test will specifically cause a few of these wild fluctuations). Indeed that shouldn’t happen and with most models it won’t happen – as we describe in reviews, the normal behaviour there is to have subtle momentary stuttering at the boundary but there shouldn’t be flickering.

[ppn7]

Thank you, i will give a try to RMA. I don’t know if i will be refund but i hope, then i will try to buy something else, maybe the 24G2SPU or BenQ EX2510(S)/Acer equivalent.

But i saw that you warned about red issue with the S version of the EX 2510

[ppn7]

Hi.

My RMA is activated. AOC is going to send me a new unit and they will pick up the old.
Really surprised by their reactivity.
I’ll keep you informed and let you know which version I’ll get. And of course if the issue is solved or not.

Thanks.

[ppn7]

Hi.

Just a quick resume. I did my RMA so I quickly receive my new unit. And I’m really satisfied that I don’t see any flickering at all. So the first one was defective for sure.

Really surprise by AOC warranty.

It’s a V1 same panel but with a new FW (firmware ?)

old one

new one

[PCM2]

That’s great to see! Really glad you’re happy with your new 24G2U and it doesn’t have the VRR flickering issue. And also that AOC facilitated the swap under warranty so smoothly for you without giving you the (in some ways inferior) BOE panel they briefly used. 😀

[skuko]

The issue with what could broadly be called ‘VRR flickering’ can manifest in various ways. It can be caused by a panel’s sensitivity to the voltage fluctuations that occur when the refresh rate changes, particularly large changes that would occur for example when the LFC boundary is crossed. VA models are usually particularly prone to this. Occasionally IPS models will have this issue, but it’s not widespread there. G-SYNC modules offer more careful voltage regulation and tighter tuning and will generally eliminate this form of VRR flickering with any panel type. It can also be caused, to a more minor degree in most cases, by slight shifts in gamma as refresh rate changes in a VRR environment. These shifts usually occur for darker to medium-dark shades when significant fluctuations occur and can even be observed on OLED models – for example, this occurs on the Dell Alienware AW3423DW even though it has a G-SYNC module. Most IPS models are free from this sort of VRR flickering as well.

Hey PCM2, long time no read.

I just got my 3423DW and i do experience this:

https://www.youtube.com/watch?v=84XVamTu_po

(not my video, but the issue is the exact same)

the title is Lost Ark, you can replicate this by just pressing escape to get the menu on screen. it darkens the rest of the image, which i assume causes this flicker.

the FPS on my end is 172 (capped via RTSS). it is eliminated by turning gsync off.

my question would be – is this the VRR flicker you mention and secondly, if it’s eliminated by turning off g-sync, is this a sign of a faulty module and should it in your opinion be grounds for a replacement?

[PCM2]

Hi skuko and welcome back,

This is the sort of VRR flickering behaviour covered in this thread and also the AW3423DW review (written and video). It’s a typical characteristic for OLED due to the extreme contrast and not related to a G-SYNC module fault. Something you might think could be corrected by a G-SYNC module with appropriate gamma correction, sadly not in this case. Game menus are a typical time when this will happen and be obvious due to large areas of static content, medium-dark to dark shades being present and the fact the refresh rate is usually fluctuating rapidly (even if just cycling quickly between a few different values).

[PCM2]

A Twitter follower has noted that the AW3423DWF suffers more noticeable VRR flickering than the AW3423DW. I’ve seen similar reports on Reddit from those with experience of both models. Coming back to what I said in my initial post on this thread about G-SYNC modules allowing more careful voltage regulation, it’s possible the ‘DWF’ has issues in that regard which are eliminated by the module of the DW. My preferred theory is that there’s actually some degree of gamma compensation on the ‘DW’. It’s a shame they didn’t include more careful gamma compensation to eliminate all forms of VRR flickering on the ‘DW’, however. It appears that other non-G-SYNC QD-OLEDs clearly suffer in a similar way. Reports suggest the Samsung Odyssey OLED G8 suffers from obvious VRR flickering, too, and I’ve received direct confirmation of this from other models (including the MSI) for those who have compared side by side with the G-SYNC Alienware.

[PCM2]

In our video reviews we like to use a specific VRR flickering test to help identify VRR flickering and highlight it in video format, even on models where it’s relatively mild. The test was hosted on GitHub and created by ‘MattTS01’, but for some reason the .exe is no longer available there.

You can download this test (OpenGL executable) here.

[PCM2]

Here’s a video showcasing ASUS ‘OLED Anti-Flicker’, now included on many of their OLED models. It’s certainly not a perfect solution, but can help in certain situations:

[Verneclover]

Hello, I have bought TCL 34R83Q monitor. it is mini led with VA panel (quite fast HVA). I knew there will be some VRR flickering since it is VA, but decided to give it a try, since I wanted 34 inch mini-led monitor and there is very limited choice on the market + VA native contrast has more potential for mini-led implementation to look good. It is actually very huge contrast improvement comparing to my old FI32Q, that is IPS with ordinary backlight.
In general, VRR flickering isn’t very bad on this monitor (however not that I really can compare it to other VA or OLED monitors, since I had only IPS monitors), but under certain circumstances it can be quite distracting. Generally, I expected that the main reason for VRR flickering will be not stable fps/frame time and also having fps around LFC border but turned out it is not all the reasons. Testing it with G-SYNC Pendulum Demo, I found one bad transition from one frequency to another – from 80hz to 81hz – it causes flicker, so if your fps is sitting in the range that includes numbers which are smaller or equal to 80 and bigger or equal to 81 at the same time, it will cause flickering even if frame time is quite flat. It’s sad, because without this single bad transition VRR flicker could be more manageable in some games. The question is – if it is typical situation for VA panels to have bad transitions for certain frequencies or I rather lost a bit in panel lottery?

from 80hz to 81hz – flickering https://streamable.com/5dbw1u
from 83hz to 84hz – no flickering https://streamable.com/9ld4fy

[PCM2]

Yes, unfortunately with VA models they sometimes have specific bands, ranges or even refresh rates which cause sufficient voltage instability to trigger flickering. So it can trigger when frame rates are quite stable in places rather than fluctuating a lot. This certainly doesn’t happen on all VA models but I have seen it from time to time. It’s possible it could vary between individual units of the same model, but some seem much more prone to it.

[Verneclover]

Thank you for the answer, probably I will try to order one more unit

[Darryl282]

Hi all,

Thought I’d post here and not make another thread as it’s related.
I’m interested in buying the Alienware AW2725DF OLED monitor. However the only thing holding me back is the VRR flicker. Now my question is this: if I set a refresh rate to 144hz or 160hz as a custom refresh rate, and not use the 360hz refresh rate. Would VRR flicker still be problematic? It’s probably a difficult question to answer.

For context I play games that are usually graphically intensive, God of War etc. My target frame rate is usually 100fps, but 165 (my current monitor cap) is always great to have.

Thanks

[PCM2]

Hi again Darryl282,

If you constrain the refresh rate and therefore reduce any refresh rate variability then you will indeed reduce VRR flicker. If your frame rate tends to fluctuate between 100 – 160fps without exceeding 160fps then it wouldn’t make a difference whether you set the monitor to 160Hz or keep it at 360Hz. It will not set itself above 160Hz anyway, under VRR. If it’s sometimes peaking above 160fps (say momentarily going closer to 200fps) and then dropping back down, you’ll be at an advantage by capping your refresh rate to 160Hz in terms of flicker reduction. In either case it really depends how stable the frame rate generally is, the content you’re observing and your sensitivity to VRR flicker as to whether it will be bothersome to you.

[Darryl282]

Hi thanks for the reply.

Ok so I think I understand it better now. We need to essentially reduce the gap, by keeping frames consistent so we don’t have high refreshrate swings. If I set the VRR range 60 – 90, would that make any difference? As I currently understand it, it would not?

[PCM2]

If it’s moving around within that range it wouldn’t help as the refresh rate would still be fluctuating. And significant swings within that range can actually trigger pretty intense VRR flickering. It isn’t just the absolute numerical drop that matters but also the actual refresh rate it’s dropping to and from – a drop from 90Hz to 60Hz may be “only” 30Hz but it would be a lot more noticeable than a drop from say 200Hz to 170Hz.

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