Mac OS Ventura + LG Ultrawide 49"

Question

Mac OS Ventura + LG Ultrawide 49"

Hello,

I was searching for a solution for my external LG display that is no longer working after upgrading to 13.0 Ventura.

I found a similar question in the dev. web Ventura - External Displays not wo… | Apple Developer Forums

I have exactly the same issue, so here are the basics:

System specs: Macbook Pro 13", 2019, 2,8 GHz Quad-Core i7

Intel Iris Plus Graphics 655

16GB Ram

Display specs:

LG Ultrawide 49WL95C-WE

The display is/was connected by USB-C PD and worked on the native solution of 5.120 x 1.440.

After updating to Ventura the screen of both devices LG Display AND Macbook are garbled.

I also tried to connect with teamviewer, and changed the resolution and also the framerate down/up but the issue stays the same.

I can run the display with HDMI, but just with lower resolution.

PRAM/SMC reset was done already.

Oh I tried different cables as well, but it might not be the problem, as the cable worked before the upgrade.

Any ideas how to solve this?

Thank you!

MacBook Pro

Posted on Oct 26, 2022 1:03 AM

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Answer 1

Best reply

LongTimeAppleUserX

Level 1

20 points

Oct 26, 2022 5:55 AM in response to asdfasdfasdf24

I have similar issues with my Dell Alienware AW3821DW. The behavior is described here - External display issues over and over aga… - Apple Community

But unfortunatelly for me even the safe boot did not work well. I am inside display detection loop and the system (probably caused by window server bug, according to console errors) is not responsive when thunderbolt to DP 1.4 cable is plugged in.

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Answer 2

digrouz

Level 1

8 points

Oct 26, 2022 1:40 AM in response to asdfasdfasdf24

well, without the picture in picture option, the screen is blinking without being able to access the menu of the screen even. So i've to plug another computer, enable picture in picture, than I can replug the mac studio and use within one of the picture.

and it used to work properly before upgrading to ventura

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Answer 3

Oct 26, 2022 2:07 AM in response to digrouz

there's a thread in the macrumors community where they say that the problem already existed in the pre release versions.

they wrote that booting in safe mode solves the issue.

i can confirm this, booting in safe mode and both displays work fine with their native resolutions.

going back to normal mode and the problem still exists.

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Answer 4

alloveru

Level 1

28 points

Oct 26, 2022 3:15 AM in response to asdfasdfasdf24

You have the same specs as me except my MacBook Pro is a couple of years older. I can get my laptop display to work by unplugging the external monitor, rebooting the MacBook, starting it back up, once logged in, plug the monitor back in... At that point my laptop screen still works, but the garbled external monitor happens.

I have been using Ventura since the beta 2, all was good until beta 7 or 8, then stopped... Appears anyone with a Mac Studio will work, but anyone with something other than a Mac display is screwed.. I have raised it as an issue every beta release, but crickets from Apple. I have this nice 49" monitor that a can't use!

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Answer 5

alloveru

Level 1

28 points

Oct 31, 2022 3:19 AM in response to matichko

For those that have found seen the other threads on this. There is a work around that was posted on MacRumours...

https://forums.macrumors.com/threads/temporary-fix-for-external-monitor-issue-over-usb-c-in-ventura.2367992/

Essentially, prior to plugging in your monitor run the following command and enter your password

sudo sleep 20 ; sudo kill -9 $(pgrep WindowServer)

Once you press enter your password, plug your monitor in, in 20 seconds you will see things flash.

You can then set your resolutions. The only thing I noticed is that my keyboard and mouse that are plugged into the monitor do not work. AND if you reboot, you will have to re run the command.