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bxs

macrumors 65816
Original poster
Oct 20, 2007
1,151
529
Seattle, WA
Subject: Using the top two TB3 ports for attaching externals and booting up from them

I'm used to booting up different versions of macOS or simply booting up an image of my internal SSD boot image from an external.

To do this I Shutdown and Restart with the Option key pressed to wait for all the bootable devices I have attached to display.

I have two self powered external SSD devices I use...

  1. TB3 OWC Envoy Pro EX - 1TB with an integral/captive TB3/USB-C cable. https://eshop.macsales.com/shop/owc-envoy-pro-ex-thunderbolt-3 and https://eshop.macsales.com/item/OWC/TB3ENVP10/
  2. TB3 Samsung Portable SSD T5 Media 500GB with - Includes USB Type C to USB-C and USB-C to A cables. https://www.amazon.com/Samsung-T5-P...ocphy=9033278&hvtargid=pla-404894224454&psc=1

  • When I attach the OWC unit to either of the top two TB3 ports on my MP7,1 and Startup with the Option key pressed the OWC unit will display but quickly goes poof in a cloud on the screen, and shortly returns, only to go poof in a cloud again. This can repeat as many as 5 times and ends up with the OWC units no longer being displayed.
  • When I attach the OWC unit to either of the TB3 ports on the stock Apple i/o card and Startup with the Option key pressed the OWC unit will display but quickly goes poof in a cloud on the screen, and shortly returns, only to go poof in a cloud again. This can repeat as many as 5 times and ends up with the OWC units no longer being displayed.
  • If I attach the OWC unit to any of the TB3 ports on my Vega II the disappearing act does not happen.
  • If I use my Samsung T5 connected to either of the MP7,1's top two TB3 ports it always displays with the Option key Startup and never goes poof in a cloud. It also works fine when attached to any of the Vega II's TB3 ports or the Apple's stock i/o PCIe card..
I've contacted Apple Tech help and they are investigating why this problem happens with the OWC unit.

Because both of these units are self powered, and maybe the OWC unit requires more power than the top TB3 ports can supply compared to what the Samsung T5 requires. But of course I dunno.

Is more power provided by the Vega II's TB3 ports compared to the top located TB3 ports ?

Notes:
  1. According to https://eshop.macsales.com/item/OWC/TB3ENVP10/ it states the OWC unit is not compatible with the MP7,1. This maybe my problem, and if so..... bummer. It maybe just an issue using the MP7,1's two top TB3 ports and the TB3 ports on the stock Apple, i/o PCIe card.
  2. However, when I connect the OWC unit to any of the Vega II TB3 ports I have no issues with the Option key Startup, and can select the OWC unit to boot up from, and the system runs just fine.
  3. I've used the Startup with the Cmd+R to reinstall the macOS and this made no difference, and the issue with the OWC unit persisted.
 
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If I use my Samsung T5 connected to either of the MP7,1's top two TB3 ports it always displays with the Option key Startup and never goes poof in a cloud. It also works fine when attached to any of the Vega II's TB3 ports or the Apple's stock i/o PCIe card..

The Samsung T5 isn't a TB3 device. It's a (slower) USB-C device... and it works with even an iPad Pro. YOu may be right about the power aspect - since this device has much lower requirements (and performance)
 
I have two self powered external SSD devices I use...

  1. TB3 OWC Envoy Pro EX - 1TB with an integral/captive TB3/USB-C cable. https://eshop.macsales.com/shop/owc-envoy-pro-ex-thunderbolt-3 and https://eshop.macsales.com/item/OWC/TB3ENVP10

  • When I attach the OWC unit to either of the top two TB3 ports on my MP7,1 and Startup with the Option key pressed the OWC unit will display but quickly goes poof in a cloud on the screen, and shortly returns, only to go poof in a cloud again. This can repeat as many as 5 times and ends up with the OWC units no longer being displayed.
...
  • If I use my Samsung T5 connected to either of the MP7,1's top two TB3 ports it always displays with the Option key Startup and never goes poof in a cloud. It also works fine when attached to any of the Vega II's TB3 ports or the Apple's stock i/o PCIe card..
I've contacted Apple Tech help and they are investigating why this problem happens with the OWC unit.

The T5 has a detachable cable on both ends. The OWC appears to be hard mounted on the drive side. So how does the cable 'dangle' in the various positions ?


I'm wondering that because both these units are self powered that maybe the OWC unit requires more power than the top TB3 ports can supply compared to what the Samsung T5 requires. But of course I dunno.

Shouldn't make that much of a difference since both should supply enough power in either mode ( presuming no hardware fault). But is plug isn't seated properly might get some variances.
 
The T5 has a detachable cable on both ends. The OWC appears to be hard mounted on the drive side. So how does the cable 'dangle' in the various positions ?
Using the top surface port isn't an issue. Using any other TB3 port is a PITA and the short captive cable is a nuismance.
 
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MP7,1 will boot not boot any other macOS version than 10.15.1+.

Have seen reports of Windows 10 and Linux running on MP7,1 already. Do not follow those closely enough to know exact versions and/or issues.
 
Just to be clear here.... I'm only using external boot images that have Catalina 10.15.3 Build 19D76 on them.

Also, as mentioned in OP, using the OWC connected to my Vega II allows the unit to perform without issues and can select it when displayed with the Option key Startup and system runs perfectly using the OWC this way.
 
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I'm really quite curious about this issue, and would like to get a more complete understanding of it as I need to figure out if it makes sense for me to return my OWC Envoy Pro EX unit for a refund.

At this time the OWC unit works flawlessly when connected to any of the USB-C ports on my Vega II, but is very problematic (that is, unusable) on the MP7,1's top case 2x USB-C ports and the USB-C ports in the Apple stock i/o PCIe card.

I've asked Apple to provide me with the power output of the USB-C ports on the case's top and in the Apple PCIe stock i/o card, and OWC for them to inform me what is the power requirement for their Envoy Pro EX 1TB unit.

I note that the OWC unit is also incompatible with several of the later Apple Mac Book Pro models (mid 2018 & mid 2019 models) as well as a Macmini8,1 (late 2018 model).

  1. Does anyone actually know what is the supplied power output to the USB-C ports on the top of the MP7,1's case is ?
  2. Does anyone actually know what is the supplied power output is for the USB-C ports in the stock Apple PCIe i/o card ?
  3. Also, is there some 'gadget' I can use to determine what is the power outputs for these USB-C ports ? What about something like this >

BTW... I have a Thunderbolt 1 Apple 27" display that I normally connect to my Vega II's USB-C port using Apple's USB-C - to - TB2 adapter and it runs perfectly. I've also connected this display to one of the top case's USB-C ports and the display works perfectly also.

Thanks... :)
 
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BTW... I have a Thunderbolt 1 Apple 27" display that I normally connect to my Vega II's USB-C port using Apple's USB-C - to - TB2 adapter and it runs perfectly. I've also connected this display to one of the top case's USB-C ports and the display works perfectly also.

Thanks... :)
Those ports are Thunderbolt 3 ports ... and that adapter is a Thunderbolt 3 to thunderbolt 2 one.

As to the problem itself:

That OWC device is known since 2018 to have trouble with e.g. the then new Mac Mini
See here e.g.: https://forums.macrumors.com/threads/mac-mini-2018-external-drives-disconnecting-tb3.2169582/
It seems to point to a power issue between the mac and the device, probably the chipsets they use don't like one another or something like that.

Power on those port is not the typical thing with a power supply that puts out a voltage and can be loaded up to a certain amount of amps before it quits. There is a separate data communication channel between the supplier and the user of the power on the bus dedicated to the power on the bus, the supplier can even change the supplied voltage depending on the handshake (between 5 and 20 Volt).

Additionally for the MP7,1:

The thunderbolt 3 ports on top and on the apple IO card are internally connected to the VEGA II card via extra connections the cards makes through the motherboard (that's needed because a Thunderbolt 3 port is only a real one if it can be used to hook up a display - so the graphics card is always involved). If you remove the MPX module and replace it with a 3rd party card: I suspect the thunderbolt 3 ports on the rest of the system will cease to work completely.

There's also the T2 chip to contend with, it should be set to allow booting of other things than the internal SSD it only allows by default.
 
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Those ports are Thunderbolt 3 ports ... and that adapter is a Thunderbolt 3 to thunderbolt 2 one.

As to the problem itself:

That OWC device is known since 2018 to have trouble with e.g. the then new Mac Mini
See here e.g.: https://forums.macrumors.com/threads/mac-mini-2018-external-drives-disconnecting-tb3.2169582/
It seems to point to a power issue between the mac and the device, probably the chipsets they use don't like one another or something like that.

Power on those port is not the typical thing with a power supply that puts out a voltage and can be loaded up to a certain amount of amps before it quits. There is a separate data communication channel between the supplier and the user of the power on the bus dedicated to the power on the bus, the supplier can even change the supplied voltage depending on the handshake (between 5 and 20 Volt).

Additionally for the MP7,1:

The thunderbolt 3 ports on top and on the apple IO card are internally connected to the VEGA II card via extra connections the cards makes through the motherboard (that's needed because a Thunderbolt 3 port is only a real one if it can be used to hook up a display - so the graphics card is always involved). If you remove the MPX module and replace it with a 3rd party card: I suspect the thunderbolt 3 ports on the rest of the system will cease to work completely.

There's also the T2 chip to contend with, it should be set to allow booting of other things than the internal SSD it only allows by default.

  1. Yes the Apple adapter is for TB3 to TB2. TB2 is compatible with TB1 so that is why the adapter is ideal for driving my TB1 27" display without issues.
  2. Yes, I'm of the opinion it's a power supply issue of some sort that is affecting the OWC Envoy Pro unit. It works perfectly for me when connected to the TB3 ports provided on the Vega II.
  3. I do have my system configured to allow booting from an external device.
  4. Thank you. :)
 
  1. Yes the Apple adapter is for TB3 to TB2. TB2 is compatible with TB1 so that is why the adapter is ideal for driving my TB1 27" display without issues.
  2. Yes, I'm of the opinion it's a power supply issue of some sort that is affecting the OWC Envoy Pro unit. It works perfectly for me when connected to the TB3 ports provided on the Vega II.
  3. I do have my system configured to allow booting from an external device.
  4. Thank you. :)
"I do have my system configured to allow booting from an external device."

Would mind letting me know how you made that configuration? I need to do that for the CCC clone I made yesterday.
 
To enable booting up from an attached external device goto https://support.apple.com/en-us/HT208198 to understand how this is configured.
Not seeing the appropriate icon to let me designate allowing external boot drive. _when I command R login, it goes directly to the administrator login and not utilities.

Screen Shot 2020-02-14 at 7.47.52 PM.png
 
Not seeing the appropriate icon to let me designate allowing external boot drive. _when I command R login, it goes directly to the administrator login and not utilities.
CMD-R while power on.
Then you get the recovery partition to boot, it's not in the system preferences.
 
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CMD-R while power on.
Then you get the recovery partition to boot, it's not in the system preferences.
I see. The CCC Boot Disk shows as an alternative HD once I make sure it is plugged into the 7.1 prior to restart and command r. I am hoping that in case I need it, it actually does boot up ^ Im afraid that it might say that you can't boot up from an external drive. I still can't find the place that lets me click allow boot up from external drive.
 

To allow your Mac to use an external startup disk:
  1. Open Startup Security Utility.
  2. Select ”Allow booting from external media.”
    Your Mac doesn't support booting from network volumes, whether or not you allow booting from external media.
  3. If you want to select an external startup disk before restarting your Mac, quit Startup Security Utility, then choose Apple menu  > Startup Disk.
 

To allow your Mac to use an external startup disk:
  1. Open Startup Security Utility.
  2. Select ”Allow booting from external media.”
    Your Mac doesn't support booting from network volumes, whether or not you allow booting from external media.
  3. If you want to select an external startup disk before restarting your Mac, quit Startup Security Utility, then choose Apple menu  > Startup Disk.
_when I startup in recovery mode ^ it does not show this+
  1. When you see the macOS Utilities window, choose Utilities > Startup Security Utility from the menu bar.
It just goes straight to the administrator login icon.
 
_when I startup in recovery mode ^ it does not show this+
  1. When you see the macOS Utilities window, choose Utilities > Startup Security Utility from the menu bar.
It just goes straight to the administrator login icon.

Then you're not doing it right.

What keyboard and mouse are you using?
 
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....
I note that the OWC unit is also incompatible with several of the later Apple Mac Book Pro models (mid 2018 & mid 2019 models) as well as a Macmini8,1 (late 2018 model).
....

If you are looking at the compatibilty tab for the product to get that info for the MBP models .... not sure why not seeing it popping up for the Mac Pro.

https://eshop.macsales.com/item/OWC/TB3ENVP05/



This new OWC product doesn't have the compatibility matrix problems the above has.

 
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If you are looking at the compatibilty tab for the product to get that info for the MBP models .... not sure why not seeing it popping up for the Mac Pro.

https://eshop.macsales.com/item/OWC/TB3ENVP05/



This new OWC product doesn't have the compatibility matrix problems the above has.


Yes, I unfortunately made myself aware of the compatibility issue just a few days ago, and after I had owned the 1TB Envoy Pro EX since Feb 2018; long before the MP7,1 was released for sale Dec 10, 2019.

Thanks :)👍 for the ref to the OWC product -> OWC Express 4M2 4-Slot M.2 NVMe SSD Enclosure
https://eshop.macsales.com/item/OWC...n=cj&cjevent=9f8f52d94f4f11ea835b01080a1c0e0e. It looks like a useful external unit for high-speed i/o for sure.

I quite like it except it requires external power, fan cooling, is too large, and is not really portable as is the 1TB OWC Envoy Pro EX unit I have currently.

At this time I plan to keep my 1TB OWC Envoy Pro EX (OWC replaced the one I purchased in Feb 2018 with their new one, hoping it might operate better with the MP7,1) as it works flawlessly when connected to my Vega II as an alternative boot device as well as staying connected (not mysteriously unmounting), even though this connection is not optimum location as are the two TB3 ports on the top of the case.
 
Turn that to MEDIUM security if you don’t 100% always have a network connection. Have heard some people unable to change from FULL > MEDIUM without network connection present. Have not personally verified that claim.
 
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Turn that to MEDIUM security if you don’t 100% always have a network connection. Have heard some people unable to change from FULL > MEDIUM without network connection present. Have not personally verified that claim.
Ahhh... I wondered about that when reading it. Thanks.

By the way ~ I had to use the (Right) command key on the Japanese Keyboard to get to the Security Utility during recovery restart.
 
Yes, I unfortunately made myself aware of the compatibility issue just a few days ago, and after I had owned the 1TB Envoy Pro EX since Feb 2018; long before the MP7,1 was released for sale Dec 10, 2019.

Thanks :)👍 for the ref to the OWC product -> OWC Express 4M2 4-Slot M.2 NVMe SSD Enclosure
https://eshop.macsales.com/item/OWC...n=cj&cjevent=9f8f52d94f4f11ea835b01080a1c0e0e. It looks like a useful external unit for high-speed i/o for sure.

I quite like it except it requires external power, fan cooling, is too large, and is not really portable as is the 1TB OWC Envoy Pro EX unit I have currently.

At this time I plan to keep my 1TB OWC Envoy Pro EX (OWC replaced the one I purchased in Feb 2018 with their new one, hoping it might operate better with the MP7,1) as it works flawlessly when connected to my Vega II as an alternative boot device as well as staying connected (not mysteriously unmounting), even though this connection is not optimum location as are the two TB3 ports on the top of the case.
I wonder if this cable can be used to extend the OWC Envoy's captive cable -> https://www.mycablemart.com/store/cart.php?m=product_detail&p=8323
 
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