Mac Pro Thunderbolt 2 ports: Using them with external hard drives? Adapter to thunderbolt 3 doesn't work

Joshua Vereen wrote:

The drives are usb 3.2. It was my misconception that Thunderbolt ports would work with these given the adapter is a USB C type and crucial’s website for the X8 states it does work with Thunderbolt 3 after some research although I only found it in an obscure part of their site (so I’m thinking isn’t correct) . I forgot that Apple continues to be proprietary. I am using them with the usb 3.0 ports and they work fine but obviously slower than I was hoping for.

It's not "Apple being proprietary."

Thunderbolt 1 & 2 lived on a Mini DisplayPort connector. PC vendors had the option of implementing TB1 & 2, but most didn't. That's on them. TB 1 & 2 supported docks, but a dock that offered extra USB ports had to do some work. An analogy would be a USB 3.0 PCIe card for a PC. Such a card contains active circuitry – it's not just a USB-A socket with a few wires running directly to PCIe socket pins.

USB-C is a "Swiss Army Knife" connector that can carry many different things: USB data, USB power delivery, DisplayPort, and Thunderbolt. When USB-C was in development, Intel made a decision to move Thunderbolt from using a Mini DisplayPort connector to being an optional ALT mode protocol for USB-C. This appears to have encouraged adoption of Thunderbolt 3/4 by Wintel PC laptop vendors, as you can now find Thunderbolt ports on many WIntel laptops.

The Thunderbolt 3-to-2 adapter is bidirectional, but only translates Thunderbolt protocol. It won't pretend to be a Mini DisplayPort on the TB2 side, or a USB-C (USB, USB power delivery, DIsplayPort) port on the TB3 side. It is an appropriate tool for some jobs, but not all jobs. To wit:

• To connect USB-C drives to an old Mac with USB-A ports, it makes sense to use USB-C to USB-A adapters
• To connect Mini DisplayPort displays to a new Mac, it makes sense to use a USB-C to Mini DIsplayPort cable

The short version is your new drive isn't thunderbolt. It's USB 3. Therefore the thunderbolt adapter won't work.

You can check this by hooking the drive up to a(your) modern mac, and then looking in your Apple Menu/About/System Report.... Then look at where you see the drive connected. I will wager (heavily) it's USB.

So, you can still use it, but you would need to connect via USB.

ThunderBolt-2 never really lived up to its expectations, except to drive six displays from your six ports.

For Rotating Magnetic drives, USB-2 at 480 M bits/sec or 48 M Bytes/sec is perfectly fast enough for all but the fastest drives.

Your Mac Pro 2013 USB-3 ports can handle 5,000 M bits/sec, or about 500 M Bytes/sec, which is not too shabby.

When you are looking at enclosures and devices, be sure you find out the speed of the device inside. 500 M bytes/sec drive inside an enclosure that COULD run at 2000 M bytes.sec is pure specsmanship. A faster enclosure can never coax the drive to go any faster.

The Apple ThunderBolt-3 <-> ThunderBolt-2 adapter supports ONLY genuine ThunderBolt devices on each side, and no other devices (displays or drives) are supported. Only a multi-drive enclosure like a Promise Pegasus is a true Thunderbolt enclosure -- ordinary drives are just USB-C, and NOT supported.

Joshua Vereen wrote:

The drives are usb 3.2. It was my misconception that Thunderbolt ports would work with these given the adapter is a USB C type and crucial’s website for the X8 states it does work with Thunderbolt 3 after some research although I only found it in an obscure part of their site (so I’m thinking isn’t correct) . I forgot that Apple continues to be proprietary. I am using them with the usb 3.0 ports and they work fine but obviously slower than I was hoping for.

All Thunderbolt 3 and 4 ports – by definition – use the USB-C connector. As far as Mac host ports go, every USB-C port that supports Thunderbolt also supports USB and DisplayPort data. That's why so many vendors say that their USB-C (USB) peripherals are "Thunderbolt compatible."

Thunderbolt 1 and 2 ports were never designed to serve as USB ports, "just" to offer external PCIe-style expansion. (And to double as Mini DisplayPorts when a Mac or daisy-chained dock detected that the device at the end of the chain did not speak Thunderbolt.) Thus, when vendors refer to USB-C (USB) peripherals being "Thunderbolt-compatible", they are not referring to Thunderbolt 1 or 2 (Mini DisplayPort) at all.

USB-C is a connector specification only....that is, it is the name of the connector. It doesn't tell you anything else.

Most external devices should have an icon next to the USB-C port to indicate which data transfer protocol is supported. If it has a lightning bolt icon, then it supports the Thunderbolt protocol. If it has a trident icon, it supports the USB protocol. If there is no symbol, then it probably only supports the USB protocol, but you should check the product documentation to be sure.

Same should apply to USB-C cables....if they support the Thunderbolt protocol, then the cable connector should show a lightning bolt icon.

Most Apple computers using USB-C support both the Thunderbolt and USB protocols...although there are a few exceptions such as the front ports on some Mac Studios.

Not actually proprietary.

This is annoying and confusing, Intel decided to make Thunderbolt 3 the same physical port style as USB c.

If you had a true Thunderbolt drive, it would work. These are hard to find, and often mislabeled.

I have gone into the Apple store and insisted on opening a third party drive labled "Thunderbolt 3" and plugging into a MacBook Pro in the store to see that connects as USB. Sorry.

Joshua Vereen wrote:

I have 6 Thunderbolt 2 ports that I would love to utilize but is this possible with modern external devices or am I stuck with the limited to almost zero thunderbolt 2 possibilities? And then on top of that what good is this Thunderbolt 3 adapter if it doesn't work ? Maybe I am not looking at the right sites or options?

You can use that adapter to connect a Thunderbolt 3 dock. I don't think anyone sells Thunderbolt 1/2 docks any more, but there are lots of Thunderbolt 3 ones.

I suspect that most of the people who buy the adapter are going the other way. They have a new Mac that came with Thunderbolt 3 or 4 ports, and they're trying to use existing Thunderbolt 1/2 peripherals, like TB 1/2 docks or the 27" Apple Thunderbolt Display.

crucial web site says UP TO 1050 M Bytes/sec (best case)

you can run it steady state at 500 on a USB 3.0 port, You are not losing much.

Hi,

I'm using Thunderbolt port for Apple Thunderbolt LED Display.

Also Using USB3.0 ports for external drives, one is SSD 1TB drive, the other is 2TB HDD which work well.