120 Hz VRR Input lag on Xbox?

Hello community! I am the owner of an OLED TV with 120 hz from LG. Now I have noticed the following. If I play on 120 hz with UHD and VRR, then the UTC on the plane deviates about 10-15 seconds per minute. If I lower the resolution, or go from 120 hz to 60 hz, then I only have a deviation of a maximum of 3 seconds. Apparently, the simulator has a problem with the highest possible resolution. I think it’s a pity, because of course I want to use the TV in the best possible way. It could also be due to VRR. Maybe it also has to do with the HDMI cable, although it is the original cable of the Xbox Series X.

Nothing to do with MSFS. 120Hz brings nothing if your xbox’s graphics can’t knock out those kind of frame rates at the resolution you play. All the duplicated frames just add more overhead for your hardware to manage.

Yes, I’ve already had contact with LG’s support. I just need to change something about the settings of the Xbox and the TV, then it should get better. I’ll test it :+1::blush:

i have a 65 c2 and i get bad gamma flicker with 120hz and vrr which is mainly noticable at night. there is apparently lots of people having issues with with the lg oled panels especially on pc. it seems to mainly occur when the tv has to compensate for inconsistent framerates. usually you get the flicker only in menus but for some games like msfs its in game. when i boot up msfs, the first press any button screen with the intro movie planes flying is jerky and all over the place which wasnt the case on my previous led tv. xbox games are usually optimized to run at a specific framerate which prevents vrr issue. would be nice if we had an fps counter on console to see what is going on

Yes it’s sometimes easy to forget MSFS is not video and performance is not significantly capped like some sandboxed games

I have exactly the same at night. but only at 120 hz, UHD and VRR. As soon as you go to 60 hz, the flickering is gone. The flickering comes from VRR. It was recommended to disable VRR…then you can also fly with 120 hz and UHD. I will test it and then let you know :+1: and VRR has a slight deviation in the UTC in the cockpit, as the FPS fluctuate

Im fact there is one: on my LG OLED I press the button with the gear symbol on the remote control.

Now this is interesting. I’ll see if this changes things for me too.

you can disable vrr, gsync and amd freesync in the game optimizer which fixes the flicker for me

So, after some tests and contact with LG’s support, I found out that 4K at 60 HZ is the best setting. At 120 hz with VRR, an attempt is made to increase the FPS. However, since the simulator supports a maximum of 60 FPS, there are problems with 120 Hz UHD with VRR and also without VRR. You notice it because the tv tries to output 120 FPS and then the picture is delayed. You can tell by the fact that the time on the plane is going further and further from the real time intention, as the FPS fluctuate. At 60 hz it is a maximum of 2-5 seconds and at 120 hz it is 15-20 seconds per minute. What still works are 120 hz at a resolution of 1440p, but 4K at 60 Hz is the better choice. At 1440p, the FPS is also reduced to 60

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Done some testing too, and came up with nearly the same:

  • the jitter on the intro movies is completely gone when switching from 120Hz to 60Hz
  • didn’t notice any impact when VRR was on nor when it was off however
  • in fact the sim seems to support more than the 60fps as I have seen 90…110fps on the little tool that is built into my LG TV
  • the biggest advantage for me now to switch from 120Hz to 60Hz is the fact that the time on the A320neo cockpit clock stays with my real clock. I tried for two hours and found just a few seconds of delay if at all. When I had set the XBox to 120Hz I usually lost 6…8 mins per hour on the Airbus clock against my real clock

What do you think?

If that was a real LED clock I could understand, the one on my “cheap” microwave runs fast because it was seemingly made for an other than European 50Hz electricity supply. For xbox that’s not very likely and yours appears to be fighting whatever HDR or similar interaction with your monitor’s settings. Try first without all the bells and whistles and then test each LG function individually.

Exactly the same, I already wrote in the upper post :blush: you can immediately notice it at the time in the cockpit. Time no longer deviates and therefore it is the best setting for an LG OLED TV to fly to 60 hz. It doesn’t run so smoothly anymore and it’s a pity to do without the 120 hz, but I can live with it well. At 60 hz, no VRR is necessary, as the TV then runs constantly at 60 fps. I don’t think VRR is useful in this setting.

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That’s what I thought too prior to actually verifying it. I assume that the thread to update the clock counter somehow gets lower priority or is even skipped when a frame is created… thus seems more likely when at 120Hz than with 60Hz where the workload might be lower.

It seems that one of the differences between a PC and the XBox is that the XBox has no real time clock/chip (hardware) and therefore time has to be calculated and kept by SW rather than just getting the actual time from a clock chip.

The reason for this is that the MSFS is programmed for 60 FPS. When we then set to 120 hz and have activated VRR, then the tv tries to play an image at 120 FPS. Then fluctuations occur and the time differs. Strictly speaking, the whole picture differs, but we only notice it at the time. If you would like to fly on 120 hz, then you can go down to 1440p. Then the simulator runs more smoothly, but the picture doesn’t look so good anymore. Even at 1440p you don’t have a delay

That I doubt as I see framerates around 90… 100 when having set the XBox to 120 and allow VRR :thinking:

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Yes, because the TV extrapolates that. That’s why time deviates so much.

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Did some more testing:

  • VRR for me only impacts the jitter of the intro movies during startup of MSFS (XBox Series X): with VRR on heavy jitter wheras no jitter when VRR is off. This is true for both settings of the refresh rate (60 or 120 Hz). When VRR is on the LG tool shows framerates of 90…100. If VRR is off then the tool shows 60 or 120 depending on the refresh rate setting

  • refresh rate: if set to 120 then the clock in the A320neo cockpit looses 5…6 mins for every hour, when set to 60 then the clock looses “only” about 30…50 sec for every hour of flight.
    For either case I do not understand why the clock is impacted by the refresh rate. This to me seems like a fundamental design flaw?

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It’s not just about the clock on the plane. As a result, I only noticed it. It also shows the height delayed and the time of day and brightness. Therefore, the height does not match the announcement of the ATC. Of course, 120 hz is best because it runs smoothly. But I prefer to fly at 60 hz and my data is more accurate. I think the clock is running wrong, because the frame rate is artificially increased to 120 fps, although the simulator is programmed to 60 FPS.