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Monterey 12.3 Beta broke second display?
- Thread starter iGeneo
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Same here. I have 2 monitors connected via USB-C, with DisplayPortVersion 1.4 only one of them was working at the time after OS X 12.3 update. As soon as I've downgraded DisplayPortVersion on both monitors to 1.2, both monitors started working fine like a charm. I've also reported this to Apple using developer feedback app. Hopefully they'll fix it.
Thanks. That got me excited but my cheapo Chinese monitors from Amazon don't have such a setting, sadly.
I have a mac mini. three monitors worked before 12.3, now just two work. The HDMI works, only one of the thunderbird connected monitors works. Do they actually test anything before shipping it?
see if you can "dumb down" your monitors to displayportversion v1.1 or v1.2. That worked for me.
Thank you as well, I had the same problem (Mac Mini 2018). I had two monitors on DP; one is maxxed at DisplayPortVersion 1.2, the other was 1.4. I downgraded and all was working again.
What an annoying bug.
Ok my situation has been a little different -- just posting this in case it helps out anyone else.
I have a 2019 MacBook Pro 16 inch and BenQ PD3220U Monitor connected via Thunderbolt. Upgrading to Monterey 12.3 overnight broke the connection between the monitor and the MacBook Pro. Tried to access the monitor's settings but actually couldn't bring up the menu without the monitor having a signal to a device (what the??) so I had to grab my (not-yet-updated) Mac mini from another room and plug that in. Ugh.
Anyway I finally got into the monitor DisplayPort settings to switch from 1.4 to either 1.1 or 1.2 as suggested but noticed it was already on 1.2. Turns out I had changed it in Dec 2020 due to a similar problem after a macOS update.
So I changed DisplayPort to 1.4 and that allowed it to connect to the MacBook Pro again. Phew! ?
I have a 2019 MacBook Pro 16 inch and BenQ PD3220U Monitor connected via Thunderbolt. Upgrading to Monterey 12.3 overnight broke the connection between the monitor and the MacBook Pro. Tried to access the monitor's settings but actually couldn't bring up the menu without the monitor having a signal to a device (what the??) so I had to grab my (not-yet-updated) Mac mini from another room and plug that in. Ugh.
Anyway I finally got into the monitor DisplayPort settings to switch from 1.4 to either 1.1 or 1.2 as suggested but noticed it was already on 1.2. Turns out I had changed it in Dec 2020 due to a similar problem after a macOS update.
So I changed DisplayPort to 1.4 and that allowed it to connect to the MacBook Pro again. Phew! ?
OMG! It works for me. Lowered to DP v1.2 on my 27" LG HDR and it worked. However, HDR is disabled. My other LG monitor is still on v1.4 and still works since it wouldn't let me downgrade. Thanks for the tips.
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Mac mini (6 core i5) with LG 32UL950 (display port V1.1), thunderbolt connection.
Monitor no longer works with thunderbolt connection after 12.3 update.
Monitor works with HDMI connection.
Thunderbolt cable tested on other thunderbolt devices, cable OK.
update.......
Disconnected display from power for 10 minutes, now thunderbolt connection working.
Odd.
Monitor no longer works with thunderbolt connection after 12.3 update.
Monitor works with HDMI connection.
Thunderbolt cable tested on other thunderbolt devices, cable OK.
update.......
Disconnected display from power for 10 minutes, now thunderbolt connection working.
Odd.
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I did the same thing that 748s did, I shut down my 14" M1Pro MacBook Pro and unplugged my LG 32UP550-W overnight. This morning, plugged in the usbc and powered on my Mac, and the monitor works??? Though the display settings were reset as the backgrounds had different backgrounds compared to before the OS update. its working for now though.
Aaaargh!
My second monitor went away, similar to lots of folks' PCs above, with the "upgrade" to Monterey 12.3 (not beta!). I have a Mac Pro 7,1 with two Apple video cards (W5700X MPX), primary display NEC PA301W and HP Z32 second display.
The symptom was "no input detected" on the second display. At first I thought the second display's cable had become defective or unplugged but that turned out to be incorrect.
I fixed it but not sure how
My approach (aka Monkeys and Typewriters) was to keep moving the USB-C connector to different sockets on the video cards until it finally resulted in input to the second monitor. I use the Displayport input to the Z32 with a USB-C to Displayport cable adapter on the PC end.
I rebooted the PC and the monitor several times each during the process.
I wonder if there's a way to optimize the connection of two monitors with the 2 x W5700X MPX setup?
Really annoying, Apple...
Tom
My second monitor went away, similar to lots of folks' PCs above, with the "upgrade" to Monterey 12.3 (not beta!). I have a Mac Pro 7,1 with two Apple video cards (W5700X MPX), primary display NEC PA301W and HP Z32 second display.
The symptom was "no input detected" on the second display. At first I thought the second display's cable had become defective or unplugged but that turned out to be incorrect.
I fixed it but not sure how
My approach (aka Monkeys and Typewriters) was to keep moving the USB-C connector to different sockets on the video cards until it finally resulted in input to the second monitor. I use the Displayport input to the Z32 with a USB-C to Displayport cable adapter on the PC end.
I rebooted the PC and the monitor several times each during the process.
I wonder if there's a way to optimize the connection of two monitors with the 2 x W5700X MPX setup?
Really annoying, Apple...
Tom
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Having same problem with full release 12.3 now, got update pushed to me today.
MacMini 2018 intel based, LG HDR 27UK850 * 2 both connected via USB-C
Only detects one screen at a time, whichever comes up first.
Did anyone figure out a way to downgrade the OS? Apple Support is no help. TimeMachine on a network drive only offers data migration and not restoring full disk so thats no help at all. Maybe there os a new beta with the problem fixed?
MacMini 2018 intel based, LG HDR 27UK850 * 2 both connected via USB-C
Only detects one screen at a time, whichever comes up first.
Did anyone figure out a way to downgrade the OS? Apple Support is no help. TimeMachine on a network drive only offers data migration and not restoring full disk so thats no help at all. Maybe there os a new beta with the problem fixed?
Agree setting DPI to v1.2 improves situation. Found this looking for solutions to display wonkiness on Mac mini 2018 with one display, an LG 35WN65C ultrawide. After install, everything seemed ok, but later display would not get video after wake from sleep. Tried HDMI connection, but didn't support ultra-wide at desired resolution. Eventually, I tried DP setting on display and surprisingly all seems ok.
What was Apple trying to fix display-wise? Monterey 12.3 seems good otherwise; iOS 15.4 is another story (lots of headaches with AirPlay to HomePods + other speakers.)
What was Apple trying to fix display-wise? Monterey 12.3 seems good otherwise; iOS 15.4 is another story (lots of headaches with AirPlay to HomePods + other speakers.)
Sigh, same problem here. Updated to 12.3 and my second monitor stopped working.
I'm using two LG 4K displays connected via Thunderbolt/DisplayPort on a Mac mini 2018. Both monitors work as long as it is the only one plugged in. How the heck does stuff like this slip through the beta? UGH.
I'm using two LG 4K displays connected via Thunderbolt/DisplayPort on a Mac mini 2018. Both monitors work as long as it is the only one plugged in. How the heck does stuff like this slip through the beta? UGH.
This worked for me. The system ended up seeing 3 monitors, one of which had a weird resolution. WTH?! It also continued to work when I plugged the HDMI cable out of the Mac Mini, leaving the DP cable in. However, this did not survive a restart.
This solved it for me. Thanks!
Nothing worked for me, I had to revert back to 12.2.1 and that wasn't easy either. If anyone is wondering here's how:
1. Download 12.2.1 from Apple CDN here: InstallAssistant.pkg and create install media
2. Boot into recovery mode. Restoring from TimeMachine doesn't work for OS anymore. Utilities->Secure boot-> Disable everything
3. Boot to bootable flash, wipe internal HDD otherwise won't install, then install 12.2.1
4. Run "Migration assistant" to restore TM "image"
This little update just costed me 1.5 days of work. I'm permanently disabling updates. Will only jump major releases.
Good luck everyone.
1. Download 12.2.1 from Apple CDN here: InstallAssistant.pkg and create install media
2. Boot into recovery mode. Restoring from TimeMachine doesn't work for OS anymore. Utilities->Secure boot-> Disable everything
3. Boot to bootable flash, wipe internal HDD otherwise won't install, then install 12.2.1
4. Run "Migration assistant" to restore TM "image"
This little update just costed me 1.5 days of work. I'm permanently disabling updates. Will only jump major releases.
Good luck everyone.
Yes, several threads there as well, with one poster consistently trying to gaslight all the others into thinking that only LG monitors are affected.
It's discussed on there in a few threads, but AFAIK there's no official monitoring of those threads so won't necessarily raise any awareness with Apple. The only way is sending direct feedback I believe.
I'm literally selling a MacBook for one of my employees and buying him a windows machine.
He's a presenter and used to connect 2 monitors to his computer and now only one will work. I can't spend 1.5 days to revert. Done with Apple. (BTW this is the second time an update broke display issues. the last time this happened was in 2020 and it took SIX MONTHS to get an update that fixed the issue. I would link the last thread but macrumors deleted it)
Apple is not worth the price anymore. The 3 windows machines we have at work are outlasting all our macs while being cheaper and easier to repair.
He's a presenter and used to connect 2 monitors to his computer and now only one will work. I can't spend 1.5 days to revert. Done with Apple. (BTW this is the second time an update broke display issues. the last time this happened was in 2020 and it took SIX MONTHS to get an update that fixed the issue. I would link the last thread but macrumors deleted it)
Apple is not worth the price anymore. The 3 windows machines we have at work are outlasting all our macs while being cheaper and easier to repair.