I believe the FileVault thing is just half the issue. Hence the second part about using an HDMI display emulator.
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Mac Mini EGPU + AMD radeon 5700 XT problem HELP
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Well, accidentally confirmed the update notification so didn't know how to back out.
Now on 10.15.5. Seems to work as before. Still no startup logo. macOS itself works. FileVault + boot security disabled still. All monitors are connected via eGPU.
As always, make sure to update with the eGPU unplugged and a monitor connected via the integrated HDMI.
Now on 10.15.5. Seems to work as before. Still no startup logo. macOS itself works. FileVault + boot security disabled still. All monitors are connected via eGPU.
As always, make sure to update with the eGPU unplugged and a monitor connected via the integrated HDMI.
I tried the HDMI emulator. It did nothing. Well, it did something: it created a second monitor in System Preferences and I had to reposition the new screen that appeared. But outside of that, nothing. The mini still hung on boot-up.
None of those solutions are ideal. The emulator runs at 1080p, 30 hz, while my eGPU runs at 4k, 60 hz. If I boot to the emulator and then switch to the eGPU through Display Preferences, I lose the OS X dock. But I think I found the issue: if I unplug my CalDigit dock before booting, everything goes fine. If both the eGPU and dock are plugged in (even in separate busses) on boot, the system hangs. So apparently the mini can't deal with more than one active TB device when it boots.
I have a TB3 multi-bay drive (which in turn has a TB1 dock daisy chained to it) and a TB3 dual DisplayPort adapter and I see no such issues. I'm not saying you dont have an issue I'm saying its more nuanced than "it can't handle more than 1 TB device"
I have heard of the CalDigit dock causing numerous issues, even kernel panics.
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Also, I think you bought the wrong HDMI dummy plug. Those are supposed to run at 60 Hz up to 5K I believe.
This is actually covered in an Apple Support document for the Mac mini 2018.
There are two Thunderbolt 3 busses in the Mac mini 2018, each one with two USB-C ports. This is the same with the four-port USB-C MacBook Pro: two Thunderbolt 3 busses.
It is probably best to plug the eGPU into the TB3 connector closest to the Ethernet port. That is Thunderbolt 3 bus 0 port 0. If you have an infrequently used TB3 device, plug that into the adjacent port. That way you are allocating as much TB3 bus bandwidth as possible to the eGPU.
I would plug the CalDigit dock into the third USB-C port from the Ethernet connector. That would put in on TB3 bus 1 port 0. At least you are allocating the first port to the dock.
I am wrangling with stability issues with my recently acquired new Sonnet eGFX Breakaway Box 550 and new Sapphire Pulse Radeon RX 580 card. It worked for about week both on my Mac mini 2018 (Mojave 10.14.6) and a Windows 10 notebook. Then the eGPU started shutting down after a few minutes of use (no load, just basic desktop graphics). It might be a faulty power supply in the Sonnet since it's happening on both systems.
A replacement Sonnet box is on its way.
I think you have the solution. I'd never thought of checking that. My CalDigit had really old firmware. I updated it and booting seems to work fine now. Thanks.
It's a 4k 60hz plug, but the mini sees it as 1080 30hz. The only way I've been able to get 60hz directly out of the mini is by using a TB3-to-DP cable into my monitor. But since I have my eGPU, that seems redundant.
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Well it turns out that wasn't the solution after all. The mini went back to its old ways of booting to blackness. If I plugged in an HDMI cable directly from the mini, the login screen was there, but then I was back to 1080p at 30 hz. Unplugging the CalDigit didn't help. So after some trial and error, I think I've finally found a compromise.
I connected my TB3-to-DP cable from the mini to my monitor. It's connected to the same bus (0) as my eGPU. Things seem to be stable now at 4k 60 hz. I've lost a few fps on some games, but I'll take that as a trade-off. I tried rendering some 4k clips in FCPX, and it was running at about twice the speed as before, and FCPX was definitely accessing the eGPU. If I run into any other problems down the road, I'll let you know. But for now it seems to be good.
I connected my TB3-to-DP cable from the mini to my monitor. It's connected to the same bus (0) as my eGPU. Things seem to be stable now at 4k 60 hz. I've lost a few fps on some games, but I'll take that as a trade-off. I tried rendering some 4k clips in FCPX, and it was running at about twice the speed as before, and FCPX was definitely accessing the eGPU. If I run into any other problems down the road, I'll let you know. But for now it seems to be good.
I have a 2018 Mac mini on 10.15.5 with a Sonnet 550 eGPU and Vega 64 connected to a single monitor via HDMI. I was also getting the black screen issue upon boot, and I had the TB3 cable plugged into the mini's far right TB3 port. I moved the TB3 cable to the mini's far left TB3 port and now I consistently get to the login screen. I don't see the Apple logo startup, but that's okay.
I've tried every port, and never had any consistency with the result. But so far my setup seems to be working.