Sonnet Breakout Box Developer Edition + 2018 Mac mini?
I a couple decades of experience with Mac and PC hardware, but am new to the eGPU world. I was under the impression that pretty much any TB3 enclosure was essentially the same (excluding power supplies, obviously) and all compatible with all TB3 Macs, so I bought a used Sonnet developer edition for my 2018 Mac Mini. My plan was to pick up a RX570 to speed up Lightroom.
Upon digging through the sonnet site, they say that the Developer edition and retail 350W "Does not support 2018 13" MacBook Pro and newer Macs". Also, they say that the 550W and 650W are Catalina compatible, except on the 2018 Mini.
Is it worth picking up a card to try it out anyways, or did I just mess up with this purchase and would be best to just resell it? If so, what enclosures are known to work with a 2018 Mini on Catalina?
I believe it should work fine. You can try connecting the enclosure even without the GPU and check System a Report > Thunderbolt to see if it’s detected appropriately.
So I went ahead and tried it with a Gigabyte Radeon RX570 4GB. It works almost 100%. I'm using the Sonnet 0.5m TB3 cable between the Mini and the enclosure, and a DP cable between the RX570 and my Dell UP3216Q monitor.
I get the Apple logo and Filevault prompt upon boot up. Shortly after inputting the password (about the time when it would normally go to desktop), the screen flashes white near the top then goes blank. If I unplug and reconnect the TB3 cable, I get the desktop and the computer works as expected. The RX570 makess a noticeable difference in Lightroom and Photoshop vs. the built-in Intel 630. I'm pretty happy with that.
Sleep mode seems to cause the computer to not recover in the same way as boot up. So if I don't power down or use sleep mode, I'm golden :). I'm not sure whether this is device-specific, or something that needs to be corrected in Catalina.
@therfman Yes this has been an issue since beta builds of 10.15 dating more than two months now. It's isolated to the 2018 Mac mini paired with Polaris eGPU. Vega and Navi cards do not suffer from this issue. I believe this is a bug in the new firmware that enables Boot Screen support through the eGPU-connected monitor. The only thing you can do is wait for Apple to fix it. In the meantime hot-plug the eGPU once the 2018 Mac mini is up and running.