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stratokaster

macrumors member
Original poster
Jul 30, 2011
81
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Dublin, IE
Since the new Mac mini is equipped with Thunderbolt3, it supports eGPUs just fine. However, after reading Apple's documentation, it seems eGPUs are not supported during boot, so if you need to enter your firmware password or boot into recovery, you're out of luck.

On MacBooks this is obviously hardly a problem because they have internal displays. The Mac mini does not have an internal display, and black screen during the boot-up process isn't ideal. It is my understanding that it's possible to use an eGPU with a display connected directly to the Mac mini, but it basically halves the performance because the data is moving both ways through the same connection.

I wonder if connecting the same display both to the eGPU and the Mac mini and simply switching inputs depending on the situation is going to be a workable solution...
 
I would really like to understand why this is a practical problem. If I'm messing with a firmware password or booting in recovery mode, whether there's eGPU support during that process is probably not real high on my list of concerns.

I'm sure that I'm missing something. What is it?
 
If you have firmware password set as an extra security step, you have to enter it every time you turn on or reboot the machine.

Unplugging the display from the eGPU and plugging it directly into the mini every time I need to reboot would be a hassle.
 
I would really like to understand why this is a practical problem. If I'm messing with a firmware password or booting in recovery mode, whether there's eGPU support during that process is probably not real high on my list of concerns.

I'm sure that I'm missing something. What is it?
Presumably because you will not have any video due to the eGPU not being available at that point.
 
This appears to be a very significant weakness in Apple's eGPU strategy. The historical advantage of Apple was the simplicity of using their products. It appears this is a step backwards in that regard.
 
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Other than OS updates, I basically never power down nor reboot my late '12 iMac, and don't intend to do otherwise with pending replacement mac-mini. I like to pickup where I left off, spread out across multiple desktops.
 
Other than OS updates, I basically never power down nor reboot my late '12 iMac, and don't intend to do otherwise with pending replacement mac-mini. I like to pickup where I left off, spread out across multiple desktops.
Same. Unless there is a power outage long enough to kill my battery backup, my Mini's don't turn off.
Some of them since 2010.
 
Other than OS updates, I basically never power down nor reboot my late '12 iMac, and don't intend to do otherwise with pending replacement mac-mini. I like to pickup where I left off, spread out across multiple desktops.

What about those who use Bootcamp, to play games for example?
 
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Can you ‘blindly’ type the password if you need to reboot? Not ideal, but gets around the problem as long as nothing out of the ordinary happens.
 
I can't get the Mac Mini to work correctly with the eGPU from Apple and 4k Monitor. I can get the eGPU to be recognized when I plug both the eGPU and the monitor to the mac mini. However when I try to correctly connect it bu having the eGPU connected to the Mac Mini and then the Monitor connected to the Mac Mini i get no display on the monitor
 
What about those who use Bootcamp, to play games for example?

Good question, and the main reason I don't use bootcamp anymore. It would be WONDERFUL if Macs could toggle between MacOS and Windows without having to reboot in-between. A VM kind-of does that but at a huge performance penalty.

I empathize with you about making switching back and forth to Bootcamp even more laborious.

My plan (switching from iMac to MM) is to add a "real" PC (e.g. NUC) and swap the egpu cable between them. (Someone warn me if this has issues).
 
Since the new Mac mini is equipped with Thunderbolt3, it supports eGPUs just fine. However, after reading Apple's documentation, it seems eGPUs are not supported during boot, so if you need to enter your firmware password or boot into recovery, you're out of luck.

On MacBooks this is obviously hardly a problem because they have internal displays. The Mac mini does not have an internal display, and black screen during the boot-up process isn't ideal. It is my understanding that it's possible to use an eGPU with a display connected directly to the Mac mini, but it basically halves the performance because the data is moving both ways through the same connection.

I wonder if connecting the same display both to the eGPU and the Mac mini and simply switching inputs depending on the situation is going to be a workable solution...

I am very interested in this question as well. One thing I am wondering about this is the difference between available eGPU solutions. (Sonnet, Akitio, BM,..) The new Blackmagic eGPU Pro version (Vega56) has one additional connector on it's back, - a new Display port 1.4.
Does this offer new options, what is changing with a Display port compared to the older 580 version?

Screen Shot 2018-11-05 at 20.11.28.png
 
Okay. This makes sense now why I am having he problems I am having. I have been trying to boot with the eGPU connect to the Mac mini and the eGPU to the monitor. Every time I get a black screen which then shuts down and I am forced to disconnect the eGPU to boot. When it does boot I enter a different start up process where I am forced to pick a starting language and then re enter passwords before it reboots again.

I tried plugging into the eGPU after the startup but that doesn’t work.


As you indicated the MBP does support the boot process as expected.
 
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I am very interested in this question as well. One thing I am wondering about this is the difference between available eGPU solutions. (Sonnet, Akitio, BM,..) The new Blackmagic eGPU Pro version (Vega56) has one additional connector on it's back, - a new Display port 1.4.
Does this offer new options, what is changing with a Display port compared to the older 580 version?

View attachment 803304

Can you share where this documentation is?
 
Can you share where this documentation is?

https://www.blackmagicdesign.com/products/blackmagicegpu/

That's what interests me is a connection from the Display Port 1.4 to a Non-Thunderbolt computer that is however equipped with a Display port 1.4. Would this be possible? Otherwise, I am not clear on the question what the new port is for, compared to the 580 model that does not have this port.

Regardless, I think its a very interesting product. I would love to hear more about this from people that got one of those.
 
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So let me see if I understand......

A Mini connected to an eGpu and then to a monitor will not work when booting normally ?

That seems odd. Why wouldn’t I have this as a normal work setup ?
 
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So let me see if I understand......

A Mini connected to an eGpu and then to a monitor will not work when booting normally ?

That seems odd. Why wouldn’t I have this as a normal work setup ?

That is correct in my setup. I never get past the black screen. Looks like no signal to the monitor because the monitor goes to black and sleeps. Works on the MBP however
 
That is correct in my setup. I never get past the black screen. Looks like no signal to the monitor because the monitor goes to black and sleeps

You have the correct cables to use I’m guessing. I hope you can find a solution. That issue you’re having might make me reconsider going with a Mini instead of another iMac.
 
A semi-workaround for that is to have one input on your monitor connected to the eGPU and one connected directly to the Mac.
I don't have a Mac Mini (yet), but I currently use my 2017 15" MBP (clamshell mode) with an eGPU when I use Win10.
I have Displayport 1 connected directly to my MBP with a DP to usb-c cable and Displayport 2 connected to my eGPU box (Razer Cover V2 w/GTX 1080).
It defaults to the connection directly on my MBP and then after I login, I switch over to the DP2 using the input selector on my monitor.
macOS (mojave) also defaults to the connection directly to my MBP.
I'd assume the Mac Mini would act the same way.
 
So has anyone figured out the correct way to set up an external GPU on the mini and, if so, what razzmatazz, if any, has to be performed when you boot?

If it matters, I'm not using a firmware code that has to be input every time that I turn on my computer, which as I understand it is where this discussion started.

If it's still hazy, maybe we'll have more clarity when @inmnbob succeeds in setting up his new eGPU.
 
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I haven’t installed a firmware password so the process it requires me to follow after an unsuccessful boot to the eGPU is strange. I will try the double connect tip but not sure how I will test test the speed yet to know if it worked
 
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