Monterey 12.3.1 External Monitor/Display Issue - No Longer Outputting Signal

I am having the exact same issue: Acer Predator XB253QGP with a Mac mini 2018. Tried with all combination of cables, HDMI, USB-C -> HDMI and USB-C -> DisplayPort. That's totally frustrating.

Please Apple fix this ASAP!

I also have the same monitor issue with my new Macbook Pro 2021. I have an old Apple monitor that worked perfectly for years with a MacBook Pro 2011 and then with my MacBook Air 2019.

I have spend 3 weeks back and forward to Apple support and yesterday dragged monitor and two computers to the Cambridge Applestore. The engineer agreed there was a problem but had no solution.

I have an old Dell monitor at an office in London that the Marbook Pro 2021 works with when plugged into the HDMI - so I am now going to have to go there to work.

I am VERY VERY unhappy with Apple and the fact that they are neither owning up to the problem or giving a date for resolution.

Philip

I am having this exact same issue. The only difference is that i actually didn't upgrade to Monterey, i upgraded the security for catalina 10.15.7. I'm still on that software and it did the exact same thing. The computer and monitor were working perfectly.

Not only mac mini...

my MBP 15" is also impacted, secondary monitor is not anymore detected - I can still manually force connect but the 4K resolution is not anymore available anyway, making it useless for it's purpose :(

Extremely annoying issue, bothering to perform basic daily work...

what was working perfectly up to 12.2, now doesn't!

This is sad, the code quality is decreasing since approx two Years. Almost every release is buggy.

Apparently Apple is more interested on correct gender speech and diversity than on bug fixing and QA/testing new releases.

Mac Mini (2018) with LG 32" 4K monitor. Worked perfectly since the computer and monitor were new. I upgrade to 12.3 and boom, all the same problems in this thread.

Apple, IT'S BEEN 10 DAYS! FIX THIS! It's a Mac Mini. I don't have an internal display. How am I supposed to even do a software update if I can't log in because the display just goes straight to black after booting?!

I have tried several of the workarounds listed here that will work sometimes or for a couple of restarts. Very troublesome and disrupts my workflow considerably.

Come on Apple!

What ever happened to "It just works!"?

Same problem here. Two acer nitro vg240Y and 2018 Mac mini i5 32g ram 512g ssd and 2013 Mac Pro 4core d300 32g ram 512g ssd.

Both Macs updated to 12.3 and I’m getting all sorts of problems here. Anything from. No cable plugged in and no signal to everything working and one sleep cycle ruining everything.

I have spent past week trying absolutely everything including an array of different cables, screen, settings and everywhere the result is absolutely inconsistent. It is easier to deal with a single monitor setup. Dual monitor works way worse and less predictable. Can’t wait for the fix or possibly gonna roll back to Big Sur… Can’t imagine how disappointed someone would be with a Mac studio since you can’t roll that one back…

Same issue. “No signal found” on monitors, and MacBook doesn’t detect external displays either.

16” intel MacBook Pro & two Dell Ultrasharp 4K monitors each connected directly via USB C cables, no dock

I updated to 12.3 last week WHILE connected to my 2x monitors in clamshell, I had no monitor issue booting into 12.3 for the very first time. But after unplugging for the weekend, shutting down and powering up, and then plugging in today - now I get the “no signal found”.

Same issue. Updated my work MBP 2021 to Monterey, and my external Dell 4K monitor no longer works via DisplayPort. It is absolutely incredible that such a bug (or is it a "feature") has not been addressed.

I wish I could change the DisplayPort version but I use a portable monitor that does not have these settings. Apple, I have now been working for 11 days with no second display and it is incredibly dysfunctional and frustrating that such a simple capability is so broken. I need my second display to work. Please please fix this.

There are a decent amount of posts talking about moving from 1.4 to 1.2 or 1.1 DisplayPort. My monitor only has 1.1 and 1.2 and switching between those doesn't make a difference. I get the same issue where the computer randomly doesn't recognize the display.

The same issue happened to me yesterday as I updated to Monterey v12.3, after the upgrade I lost video to the screen using the DisplayPort on a MAC mini (2018). The monitor I am using is a dell s2721dgf. I never had an issue with the DisplayPort until I did the upgrade. I was able to get the monitor to work using HDMI instead of DisplayPort. I prefer to use DisplayPort over HDMI, hopefully there is a solution to this problem soon.

I am using a USBC thunderbolt to DisplayPort cable which was highly recommended to use with the Mac mini.

Hey Apple, what's wrong with this once great company?

Same Issue here. MBP 16“, Intel, Late 2019.

hp U32 4k HDR Monitor. USB-C connection.

I need the stuff to work and not to have fun. I have been massively disabled in my work for almost three weeks. When will this error finally be corrected?

With 12.2, I ran my Karaoke night with two HDMI cords plugged into my USB bus, as I have been doing since before I got my M1 iMac. I went to run it with 12.3, and now my Mac does not give me any options in System Preferences/Displays. Well, now I can move my mouse to my iPad, but that's not what I need. I need my Mac to see my external displays!