MBA M1 External TB SSD Connected to Apple TB Display?

[theMotoMan]

Hey folks, I'm not sure where exactly to post this question, so I am starting here in the M1 forum. If suggested otherwise, I am glad to move it.

TLDR; I can't get a TB3 external SSD connected to the back of my 27" TB Display via a TB2->TB3 adapter.

I have an M1 MBA connected to an Apple 27" Thunderbolt display via the Apple TB2->TB3 adapter. That works great! I also have a Wavlink external Thunderbolt 3 NVMe drive that works great when connected directly to the MBA. It does connect in the TB3 mode as reported by the System Information app. The speed is pretty good; I'm getting 1500 MB/s Read and 2200 MB/s Write.

Since I have one of my two USB4 ports connected to the Display and the other one connected to a power brick, I was thinking about connecting the external TB drive to the back of the TB Display, which has a TB2 port. I bought an Apple .5M TB2 cable and connected that to the display and using another Apple TB2->TB3 adapter connected that to the TB cable and the external TB SSD that uses a USB-C connector.

In short, it doesn't work. The MBA does not see the drive at all, nor does it light up the green power bulb on the drive. I know the Apple TB2->TB3 adapters are bidirectional, so I would expect this to work. Has anyone made something like this work or know if it should work? I tried another TB2->TB3 adapter in case mine was bad, but that made no difference. I have nothing to test the cable, but it was new.

Thanks in advance!

 

[Amethyst1]

In short, it doesn't work. The MBA does not see the drive at all, nor does it light up the green power bulb on the drive. I know the Apple TB2->TB3 adapters are bidirectional, so I would expect this to work.

The TB2<->TB3 adapter cannot supply power to a Thunderbolt 3 drive. You either need to connect the NVMe drive to a powered Thunderbolt 3 dock (and then connect the adapter to the dock) or - if possible - connect an external power supply to the NVMe drive.

The 27" Thunderbolt Display is a Thunderbolt 1 device to boot, so daisy-chaining the SSD to it might also slow down the SSD. So it might not be a good idea to do it.

 

[theMotoMan]

The TB<->TB3 adapter cannot supply power to a Thunderbolt 3 drive. You either need to connect the NVMe drive to a powered Thunderbolt 3 dock (and the adapter to the dock) or - if possible - connect an external power supply to the NVMe drive.

The 27" Thunderbolt Display is a Thunderbolt 1 device to boot, so daisy-chaining the SSD to it might also slow down the SSD.

Thanks Amethyst1, I had not considered that, but it make sense. BTW, I thought the Apple TB Displays were TB2, since the connectors are TB2. I will likely get a TB3/4 dock, but they are a bit pricey.

 

[Amethyst1]

BTW, I thought the Apple TB Displays were TB2, since the connectors are TB2.

TB1 and TB2 use the same connector (the same as MiniDisplayPort). The Thunderbolt Display was released in 2011 (and never updated/refreshed). TB2 only came in 2013.

 

[Amethyst1]

Does your NVMe drive have a second TB3 port? If so, you could try doing it the other way round, i.e. daisy-chaining the display to the NVMe drive (MBA-->NVMe-->TB2-to-TB3 adapter-->display).

 

[joevt]

Thunderbolt 1 of the Thunderbolt Display will limit the NVMe to ≈750 MB/s (some number less than 10 Gbps).

Another option is to add more Thunderbolt 4 ports using a Thunderbolt 4 hub or dock.

 

[Amethyst1]

Thunderbolt 1 of the Thunderbolt Display will limit the NVMe to ≈750 MB/s (some number less than 10 Gbps).

What if the display were daisy-chained after the NVMe?

 

[joevt]

What if the display were daisy-chained after the NVMe?

Then the NVMe will have normal performance and the Thunderbolt Display will be usable.
There aren't a lot of NVMe enclosures with two Thunderbolt ports
https://www.amazon.com/JEYI-ThunderDock-ThunderBolt3-ThunderBolt4-TYPEC3-1/dp/B08W3WVSND

which is why I suggested the Thunderbolt 4 hub/dock option.
https://thunderbolttechnology.net/p...&field_prod_tb_version_value_many_to_one=tbv4

You could put an NVMe in any Thunderbolt PCIe expansion chassis.
https://www.sonnettech.com/product/thunderbolt/pcie-card-expansion-systems.html

 

[theMotoMan]

Does your NVMe drive have a second TB3 port? If so, you could try doing it the other way round, i.e. daisy-chaining the display to the NVMe drive (MBA-->NVMe-->TB2-to-TB3 adapter-->display).

Unfortunately, it does not, but that is a great idea. Thanks!

 

[theMotoMan]

Thunderbolt 1 of the Thunderbolt Display will limit the NVMe to ≈750 MB/s (some number less than 10 Gbps).

Another option is to add more Thunderbolt 4 ports using a Thunderbolt 4 hub or dock.

Thanks joevt. I did not realize the 27" TB Display was TB1 until Amethyst1 told me. That is something that I wish I had investigated before I dropped cash on the extra TB adapter and cable. I will either have to revert back to my USB enclosure for my NVMe or buy a TB4 dock.

The USB enclosure I have is a USB 3.1 Gen 2, capable of 10Gb/s, but alas these blasted M1s connect at Gen 1 speeds, hence the reason I bought the TB enclosure. BTW, I did have this connected to my M1 Mac Mini and all was well with the world, but selling the house and moving forced the sale of the Mac Mini and now I am running solo with the MBA.

 

[theMotoMan]

Then the NVMe will have normal performance and the Thunderbolt Display will be usable.
There aren't a lot of NVMe enclosures with two Thunderbolt ports
https://www.amazon.com/JEYI-ThunderDock-ThunderBolt3-ThunderBolt4-TYPEC3-1/dp/B08W3WVSND

which is why I suggested the Thunderbolt 4 hub/dock option.
https://thunderbolttechnology.net/p...&field_prod_tb_version_value_many_to_one=tbv4

You could put an NVMe in any Thunderbolt PCIe expansion chassis.
https://www.sonnettech.com/product/thunderbolt/pcie-card-expansion-systems.html

The Caldigit Element would be my dock of choice if I were to get one.

 

[joevt]

The Caldigit Element would be my dock of choice if I were to get one.

I like it because it's about the same size as other Thunderbolt 4 hubs but it includes internally a 4 port USB 10 Gbps hub to add three more type A ports.
It's fine if you don't need it to do Ethernet or SD cards - or you could just connect some USB to Ethernet or SD card reader adapters which is what the full sized Thunderbolt 4 docks do internally (it's all USB except for downstream Thunderbolt 3/2/1 devices).

EDIT: fixed pronoun in first sentence