Thunderbolt 3 to Thunderbolt 2 Adapter Not Working??

Question

Thunderbolt 3 to Thunderbolt 2 Adapter Not Working??

This was from an old thread...

I have a OWC dual enclosure with TB2 and USB 3.1 Gen 1 ports. Time Machine runs on the HDD and I had used the SSD as a boot disk on my '15 iMac.

Replaced the iMac with a Mac Mini M2, connected the enclosure using the same cable to the Apple TB2--> TB3 adaptor, plugged adaptor into port on MM and reformatted both disks (not the TM backup right away).

Using the enclosure's TB2 port, everything worked well for a week or so and then the disks started ejecting, usually when display sleeping, but not always. Fast forward, spoke with Apple Support many times, tried all different settings, etc. The next step is for them to send to Engineering.

On a whim, found a USB 3.1 to USB-A cable and plugged into the enclosure and the MM. So far, no ejections (couple of days).

Is the Apple adaptor faulty or not engineered for what it says it should do? I would think if engineering issue, it would not have worked from the git go.

Mac mini, macOS 15.0

Posted on Sep 27, 2024 8:47 AM

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Answer 1

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den.thed

Level 10

82,636 points

Sep 27, 2024 9:29 AM in response to Marc Schreiber

There is no gain in using the enclosures Thunderbolt 2 connection over using it's USB 3.1 connection.

Reason being, is that a USB 3.1 connection is plenty fast enough for the SATA 500MB/s SSD that enclosure accepts.

Just make sure that you have a USB 3.1 cable or adapter and cable, instead of a USB 2.0 cable or adapter and cable.

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Answer 2

tbirdvet

Level 6

14,567 points

Oct 21, 2024 4:22 PM in response to Marc Schreiber

Connection design is not the issue as long as the port supports USB3.0 or higher.

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Answer 3

den.thed

Level 10

82,636 points

Oct 22, 2024 8:51 AM in response to Marc Schreiber

Sorry for posting an image of a High Speed USB-A to USB-C cable earlier.

The OWC Dual drive has a High Speed 3.1 USB-B type port.

So your fine for speed, if you are using blue High Speed USB 3.1 to USB-A cable.

or a blue High Speed USB 3.1 to USB-C cable with the M2 Mac mini.

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Answer 4

Oct 22, 2024 4:55 AM in response to Marc Schreiber

One possibility may not be the adapter but the cable being used. It is not obvious but cables can go bad even if not being moved at all once connected. Since you were using a TB2/TB3 adapter, I assume the cable is a Thunderbolt2 cable which has active electronics and can go bad.

As for the USB interface, you need to make sure the USB-A to USB-C cable does support USB 3.0 or higher. Many of these types of cables can be just charging cables which will only support USB2. As others have said, transfer speeds with USB3 (of which there are a lot of variations) will be more than fast enough with a SATA SSD in the enclosure and definitely fast enough for any spinning disk drive.

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Answer 5

den.thed

Level 10

82,636 points

Oct 21, 2024 1:00 PM in response to Marc Schreiber

USB-C to USB-A cables with the blue insert are plenty fast enough for SATA 2.5" SSDs.

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Answer 6

Oct 21, 2024 10:35 AM in response to den.thed

Sorry for the delay in responding; multiple hurricanes got in the way.

So I have been using the USB 3.1 port with a cable that has USB-A into the Mini and I have had no ejections. But, isn't the data transfer speed impacted negatively by the USB-A connection? Is there such a cable as USB 3.1 --> USB-C? And would that help?

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Answer 7

den.thed

Level 10

82,636 points

Oct 21, 2024 5:22 PM in response to Marc Schreiber

Marc Schreiber wrote:

OK, but I am using a USB 3.1 to USB-A. From what you are saying, the USB-A connection does not severely impact data transmission, either with a -C or -3.1 cable.

That is correct as long as you are using a USB 3.0 or 3.1 cable.

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Answer 8

Oct 21, 2024 1:42 PM in response to den.thed

OK, but I am using a USB 3.1 to USB-A. From what you are saying, the USB-A connection does not severely impact data transmission, either with a -C or -3.1 cable.

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