White screen with EGPU only connected

Sonnet couldn't replicate this issue on their Mac mini so this may be an upgrade issue. Until someone reinstalls from scratch we may not know. I'm more debating waiting for the update that usually comes in the first few weeks.

I did a full reinstall from scratch to an empty drive. This does not solve the problem, after installation the first thing I am greeted with was the dreaded white screen of death.

Also, the first 15.1 dev beta does not seem to fix the problem. :(

I also have a 2018 mini with the Sonnet Breakaway Box RX580. When I get the all white screen at login, I unplug the egpu from the mini - wait 5 seconds - plug it back in to the mini and all is fine. Still a pain, but no need to have anything plugged in by HDMI this way.

Don't forget to make a ticket with Sonnet and Apple. Maybe with enough people they'll actually try to fix this issue.

Btw, if you keep your monitor off during boot and turn it on when the login screen is up you won't have any issues. Otherwise, you'll have to power off for five seconds to get it going.

Just thought I'd add to this. I am using a HP Omen eGPU box and running the latest beta (to try and fix the white screen) and still having the same issue as everyone else. I am currently booting using the HDMI connected to the same monitor and then logging in (I found have to be logged in to switch) then remove the HDMI. My setup worked flawlessly in Mojave. I find it ironic that this firmware update designed to aid eGPU boots has actually broken so many working eGPU setups using RX580. Let us hope this is fixed in a beta (and then I am going back to Mojave as also removed SMB1 support that my NAS uses).

This is also a problem Sonnet Breakaway Boxes/Mac Mini/Catalina with Radeon RX 480. It appears that this is possibly a universal issue with Mac mini/Catalina and all egpu boxes. I read that "some high-end" Radeon video cards may work but I can't verify this.

I do know that many (if not all) of the Radeon video drivers are native to Mojave and Catalina so the eGPU manufacturers are unable to patch them. Even tho Apple shows certain configurations work with Catalina...they may not. Apple Engineering will need to provide a fix with an update to Catalina. Let's hope they will do so soon. I know a lot of unhappy people (some gamers and some advanced video users) who need their egpu/Radeon cards to work like they did with Mojave. Reverting back to Mojave from Catalina is a major pain and may cause other unintended consequences.

It also doesn’t work (tried it) as Catalina pushed a firmware update. I should add this was a full fresh from external USB install of Mojave so it is 100% the new firmware. Is there any way to roll the firmware back on Mac OS? I doubt that is easy but worth asking!

Some of us are not on the Beta Program. Reason being that we only have one Mac system and can not afford to risk a Beta version with our only machine. We all trust Apple to provide us with a stable Mac OS update when they say it is ready for prime time - unfortunately, something slipped thru the cracks with Catalina.

That being said, I would be interested in hearing from someone who is on the Beta program if a Beta release squashed the bug!

Also agree 100% I’m fortunate to have other older macs to use but i shelled out on a i5 model 2018 then paid for an official Apple dealer to upgrade ram to keep warranty (£270 as in UK) then got an eGPU with RX580 and a 1TB SSD. I went this route as i prefer my own display and GPU upgradable so they brick it for me after doing it all right!

A slight inconvenience doesn’t cause your GPUs fan to hit levels I’ve not even heard after hours of gaming. I don’t use the term brick lightly. I really do worry keep trying this post update is going to fry my whole setup with an overload. I’ll wait. Fair enough regarding firmware but you can downgrade a bios or flash firmware on a Mac. I’ve also heard of people downgrading the old Mac Pro’s so it’s viable is apple released the older firmware.

Even after the two "Updates" from Apple to the official Catalina release (Now October26,2019) I have the same issue with the Radeon RX580 in the Sonnet Breakaway Box presenting the "White Screen of death". Reported the problem to Apple this morning. No suggestions given. Workaround of cycling the power off/on on the Sonnet Breakaway box enables the EGPU. While this is a bit of a pain, I prefer it to having to have an additional monitor connected to the HDMI port, which does work too.

My situation was similar on a 2018 Mac mini with a Radeon RX580 in an OWC eGPU, which is listed among the supported devices on Apple's website. Upon update to Catalina, the eGPU was not recognized at all. This was true booting into Mac OS and Windows 10 via Bootcamp. I connected to external display via HDMI, which worked fine on integrated graphics. I tried several fixes until I found what worked: opening the eGPU case, unplugging the power directly to the graphics card, pressing the card to be sure it was seated, and re-inserting the power cables. When I put the system back in place, it worked the same as it did under Mojave. (It also worked again under Bootcamp like before.) I still have problems: upon first boot, the second monitor is not recognized in Mac OS X. I need to put the computer to sleep and then wake it in order to get the second display to work. Everything works flawlessly in Bootcamp running Windows 10. There is a bright red screen during the boot up sequence to Catalina, but the displays work thereafter.

I have the same problem with my Mini2018 with Sonnet and RX580. If I boot with the egpu connected I get a blank screen on any monitor connected to the egpu and nothing seems to make it work. If I connect my monitors directly to the mini it works fine. I just installed 10.15.1 with no improvement.