eGPU (Sonnet) not longer working with a 2018 Mac mini after upgrading to Sequoia 15.4

[Keblar]

The location of those drivers are Macintosh HD>System>Library>Extensions.
View attachment 2508865
EDIT: Was your eGPU plugged in last time you updated MacOS? If not, I wonder if MacOS failed to install the AMD drivers because the eGPU was not plugged in at the time. That would actually explain why it's working in Windows and not MacOS.

Sorry @Engender I was looking inside the wrong path. The extensions do show up when my Mac is not connnect to my eGPU. Here is a screenshot.

Generally speaking, I would boot without the eGPU connected when a software update was available to install in macOS. However, there were instances that I would forget to disconnect the Sonnet, and hit restart. My Mac would not display image but still be updated just without display. I would have to shutdown my Mac and restart. Then check if it was installed in About this Mac. it was always okay and the Sonnet booted normally every time this was done.

I even recall this one time, that the eGPU was on. It went and did the update displaying the process until the end. I mean, Apple logo, progress bar and remaining time.

In bootcamp under Windows 10, this was not necessary at all. I would install software updates without turning off the eGPU, and it went okay without any problems.

Can you just disable extensions in modern macOS releases? lm thinking Mac OS 9 days. Then test if external hardware would boot alongside your Mac

Im just crossing my fingers 15.5 will fix this mess.

 

[frou]

EDIT: Was your eGPU plugged in last time you updated MacOS? If not, I wonder if MacOS failed to install the AMD drivers because the eGPU was not plugged in at the time.

I would think all the drivers Apple ship officially (incl. for AMD GPU) are part of the read-only OS volume, and don't get added/removed in a personalised way.

 

[Engender]

I have three monitors—two connected to my eGPU and one connected directly to the Mac Mini via HDMI. That way, when I do a software update or need to access the recovery partition, I don't need to mess with the monitor connections. Can you set it up that way Keblar before you updated to 15.5? Even though you have the drivers, I wonder if MacOS is not booting up with them because MacOS isn't aware that you have an eGPU as it wasn't connected during the last update.

 

[Keblar]

I have three monitors—two connected to my eGPU and one connected directly to the Mac Mini via HDMI. That way, when I do a software update or need to access the recovery partition, I don't need to mess with the monitor connections. Can you set it up that way Keblar before you updated to 15.5? Even though you have the drivers, I wonder if MacOS is not booting up with them because MacOS isn't aware that you have an eGPU as it wasn't connected during the last update.

 

[Keblar]

I’ll try to find other monitors. But remember that I did clean install of Mojave and Sonoma when this issue appeared. All fresh and untouched. It would still crash. I have discarded a number of things, but at this stage, I’m about 90% sure it is firmware related introduced in 15.4

I searched in Mr. Macintosh website and 15.4.1 did not change the firmware or the T2 bridge thing. Hopefully 15.5 changes that.

Also, I have asked people that have been trying the RC of 15.5 (no reply, it seems everyone is using Apple Silicon these days).

 

[bzgnyc2]

I’ll try to find other monitors. But remember that I did clean install of Mojave and Sonoma when this issue appeared. All fresh and untouched. It would still crash. I have discarded a number of things, but at this stage, I’m about 90% sure it is firmware related introduced in 15.4

Based on what you've shared so far, I would not rule out a hardware issue with the Sonnet box.

Have you tried connecting the same setup to another Intel-based Mac and/or Boot Security=None / Allow booting from external disk?

 

[Patrice Brousseau]

My Breakaway Puck is still ok after 15.5 and a newer T2 firmware, knock on wood!

 

[throAU]

Any suggestions?

Roll back to backup and report bug

 

[bzgnyc2]

Roll back to backup and report bug

Since he already tried older OS, the issue is either in the firmware included with the update or a coincidental hardware issue with his device. If the former, he would have to downgrade the firmware which is not a trivial operation with modern Macs.

 

[Brian33]

If the former, he would have to downgrade the firmware which is not a trivial operation with modern Macs.

I could be wrong, but I'm pretty sure I had read at eclecticlight.co that it was impossible to downgrade firmware on Intel-based Macs. For the OP's sake, hope the firmware isn't the issue. : (

(On M-series Macs it can be done with a DFU restore using another Mac.)

 

[bzgnyc2]

I could be wrong, but I'm pretty sure I had read at eclecticlight.co that it was impossible to downgrade firmware on Intel-based Macs. For the OP's sake, hope the firmware isn't the issue. : (

(On M-series Macs it can be done with a DFU restore using another Mac.)

I think that has been resolved after Catalina on T2 machines -- see postscript in the following:

Don’t try reverting a T2 to older firmware

If you’ve been running pre-release firmware on your Mac’s T2 chip, trying to revert to a release version could brick it.

eclecticlight.co

Then it was my understanding the process for T2 is now similar to Apple Silicon:

How to Restore BridgeOS on a T2 Mac + Boot a Mac to DFU Mode

macOS Update brick your Mac? This article will show you how boot to DFU Mode and restore BridgeOS on a T2 MacBook Pro, Air, iMac Pro, Mac Mini & Mac Pro!

mrmacintosh.com

Note that if one's down to this option:
Actions > Restore = Reinstall BridgeOS & ERASE OS AND USER DATA

it's going to be tough as, besides the obvious trauma, the next step would be to reinstall the OS which as I've noticed lately that MacOS will grab the latest firmware available even if you are installing an older OS (i.e. reverting your firmware back to the one you just downgraded from).

Personally, I find it a bit excessive that Apple updates the firmware with every ~ bimonthly OS update. The whole idea of firmware is that it was software that didn't need to change that often. I also don't think their installers should update the firmware to anything newer than what originally shipped with the OS being installed. Then I don't think they should make it so hard to downgrade...