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Queru

macrumors member
Original poster
Jul 29, 2019
53
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EDIT - story recap:

1. I have Mac Mini with eGPU and LG 27 inch 4K monitor (exact specs below in original post).

2. I performed update from Mojave to Catalina.

3. After setup on first launch of system my monitor went white-screen.

4. I performed shut it down And turned machine on again-> managed to get into MacOS and bootcamp with no problems.

5. Next day - can‘t start macOS, through eGPU I get white screen, through iGPU of Mac Mini directly to monitor - screen is black, shows no signal.

6. I managed to plug my old 21 inch 1080p Asus monitor - managed to run the system only through HDMI via iGPU, via eGPU still had black screen.

7. I tried to reinstal Mojave, had tons of problems as every time I plugged bootable USB it either didn’t see it or tried to reinstal into Catalina.

8. Finally I installed Mojave while using this old 21 inch monitor. I was happy stuff worked again, or I thought it did.

9. I plugged in my old setup that used to work on Mojave just fine and BOOM - again white screens. Plugging back to 21 inch - can’t get into system. Couple of option+command+P+R times, managed to run system via iGPU to 21 inch screen and via eGPU to 27 inch. I gave it time to update all drives in the background, then turn off, and again try to launch with eGPU to 27 inch LG as only monitor - FAIL again.

10. Tried to go back to 21 inch as main screen - 21 via iGPU goes green, 27 via eGPU goes white (Photos later in this topic).

11. I somehow managed to get into Bootcamp. At the moment Windows run on Mac mini far better than MacOS which is unusable right now. THIS IS RIDICULOUS. I’ll probably stay on Windows until it’s fixed then.

12. Seems like Mac mini started to like my 27k, but only through HDMI with using iGPU. Each time I try to run it with eGPU it goes white-screen. eGPU works flawlessly with boot camped windows 10. And all of this despite going back to Mojave. Catalina damaged something, not sure what tho. - seems like firmware update that persist despite clean macos install.

13. More than a month later (13.11.2019) and I still can use Mac mini reliably only with bootcamped windows. This is pathetic.

lI did call apple support when first problems occurred, I tried to call them now but they don’t answer.

I’ll keep this part updated as I struggle. This far - 7 hours wasted to bring it back to life. Thank you Apple for ruining my experience.


ORIGINAL POST:
Important notice, especially for those using eGPU - Catalina may break your Mac mini.

My setup - Mac Mini 2018 with i5, 16gb ram, 256 gb internal storage
eGPU - Sonnet Breakaway Box 550w with Sonnet Sapphire Pulse RX 580.
Monitor - LG 27UK650-W

After updating to Catalina on firsts boot I had white screen and everything frozen at that point. I force shud-down machine and it worked for couple of hours. Today I can‘t boot into macos - on eGPU mac freezes in white screen after apple logo, on iGPU - nothing is even displayed on my monitor. I was on call with support, they hear about it second time, no fix yet. Display should work as I managed to get into safe mode via HDMI on iGPU two times. Tho It’s unconsistent, couple of times it fails to boot into safe mode before I manage to get in.

Now I try to make bootable USB, but have no idea how I’m gonna instal macOS while my screen does not work.

If any of you experienced this please share tips. I can’t boot into recovery on iGPU, on GPU I loose display after 5 minutes of installation, there’s “no signal”.

EDIT: Monitor is LG 27 inch 4K
 

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Tried Everything, seems like a problem with LG model. I plugged my very old 21 Asus monitor via HDMI, this one works - I’ll try to downgrade to Mojave if I’m able to....
[automerge]1570640467[/automerge]
Tried to recover to system that Mac Mini was shipped with - effect on picture... so I’m still stuck. Downloading bootable mojave in a meantime to put it into USB in hope of recovering from this mess.
 

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Another update - reinstalled Catalina - still does not work properly.

And yes, Catalina makes me unable to use eGPU even with old 1080p monitor. So it's not only related to my LG 4k. The only thing that works is iGPU through HDMI to 1080p monitor. Waiting for Mojave to download to make bootable USB.
 
Lots of display issues being reported with the Mini, I had issues also, as soon as Catalina installed and the device restarted signal was lost to both monitors. Eventually figured out it was the HDMI to USB-C cables. Plugged in HDMI to HDMI and it worked again. Those with DP to USB-C seem to have no issues so I have ordered a couple to see if they work.
 
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Holy... ok so I'm beyond pissed.

I made bootable mojave USB disk. Mac doesn't see it in bootable disks list in preferences.
Anyways I reboot, press option to get to the panel to choose disk - cool, it sees the USB with Mojave then.
I go into Mojave disk and hey - BOOM it wants to instal that cancer Catalina.

Come on Apple, what have you done to my mini.... I can't even go back to something stable and am cursed with this piece of flamingo... can someone help me?

FFS, I never liked Windows that much, but always managed to get along with tweaking stuff. Here I can't even get anywhere beyond this mess. Like okay, as long as macOS works it's nice and butter, but when stuff happens, it's FUBAR.
 
Glad I came across this thread !
Similar issues . I use my mini at work with a 24” LG 4K monitor .
When I power up in the morning nothing on screen . Apple support said unplug everything and reboot and it did eventually come on.
Next day wouldn’t , no matter what.
Called Apple again - take it to an Apple store (1 hour away) no thanks .
Took the mini home with the intention of reinstalling Mojave- worked straight away . This was on my old Dell 24 HD monitor.
Back in work - same old story . If I’m lucky it would come on screen after an SMC reset.
Not today .
So after reading about monitor issues on here I connected it into a HD tv - worked first time .
Feedback sent to Apple.
Just going to put up with old monitor for now and hope for a solution soon.
 
Another update

I managed somehow to install Mojave. Happy seeing ssystem installed, while I lost some recent files that fortunately were not important, I turned Mac off and plugged my old setup so eGPU and LG monitor. Turned Mac on - no visual. Tried again - Imidiately after apple logo I got spinning globe and prompt to chose my WIFI. After doing it it fails to do anything more. So I turned it off, plugged old monitor because it worked and - same problem, spinning globe and failing connection.

I’m trying to figure out what to do now. If I fail to push through with Mojave I’ll call apple support again. This is horrible.
 
Mojave in, welcome back white screen. I am able to get into login screen, put password, it starts to log in and then white screen like this:

Waiting for apple support to help me go through this mess, it’s unbelievable how bad it is.

EDIT: look at all this fun on the second photo.
 

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Despite reinstalling to Mojave and cleaning the partition I still have problems. I’m actually surprised that despite reinstalling the system clean some corrupted files would somehow remain to result in problems still occurring. Any advise how to do a complete clean install or reinstall drives?
 
Same here. Bricked. Restoring to Mojave from TM didn't work, caught an error. Absolute mess. Now trying to install a clean version of Mojave.

**** Apple for releasing this **** bugged out and not at all ready for prime time.
 
My 2018 Mac mini got bricked with the *first* Catalina Developer Beta. No excuse for this to keep happening. Sorry that some of you have to go through this too.
 
Mojave in, welcome back white screen. I am able to get into login screen, put password, it starts to log in and then white screen like this:

Waiting for apple support to help me go through this mess, it’s unbelievable how bad it is.

EDIT: look at all this fun on the second photo.
Try to unplug the monitor cable and plug it back in after a few seconds. Does that clear the white screen?
 
I’ll definately try it when back home for weekend and get back to you with info whether it works or not. Need to try both resetting NVRAM before reinstall and your proposal.
 
Unpluging and plunging monitor again didn’t help, even switching between outputs doesn’t help. Using 2 monitors doesn’t help. Only way I can use this thing in macOS is with 1080p monitor on iGPU.

I’m gonna try triple NVRAM reset before install if I have spare time in coming days.
 
OP:

Something to try. Sounds off-the-wall, but try it anyway.

Just unplug the Mini from the wall and let it sit 10 minutes.
Then plug it back in and try again.

Results....?
 
Just to add to this thread and to catch any folks who haven't yet installed the most recent security patch for Mojave, it appears that the problem may not be limited to Catalina. I'm still on Mojave and had not had any problems with my Mini running an egpu. I just installed the security update for Mojave from a few weeks ago and...bam. White screen. FFS Apple. It's not like you've got an endless variety of hardware to test.
 
@Fishrrman not working.
I’m using windows only on my Mac mini for last couple of weeks. Still waiting for the fix.
 
Temporary fix that lets me use macOS collected from other threads and here:

1. USB-C -> Display Port dongle
2. Screen is dark but I blindly write password and press enter
3. Screen wakes up after successful login

It fails from time to time and I need to do NVRAM reset and then works again. No success to run it with RX580 in eGPU.

Just great, apple, I'm amazed. How long it is now? 1,5 month?
 
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