Questions & Answers for Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter

I have a 13-inch 2018 MacBook Pro, the Thunderbolt 3 to Thunderbolt 2 adapter allows me to connect to the thunderbolt display, and the graphics are working fine.

The USB ports also functioned without a problem.

Updated:

To get the ethernet on the display working, I had to disconnect the USB-C adapter, delete (AFAIR) the Thunderbolt Bridge from the network preferences, and then reconnect the adapter.

• Answered by Patrick M from Portland
• 16/08/2018
• Flag as inappropriate Answer (can i connect my new 2018 macbook pro to my 2012 thunderbolt display)

I have a Precision 5520 with a USB Type C port which supports Thunderbolt 3 and I have successfully connected my Apple Thunderbolt display (circa 2015) to my laptop using the adapter.

• Answered by Srinath A from Chapel Hill
• 14/05/2019
• Flag as inappropriate Answer (Can I use this to connect the Thunderbolt Display 27in to a Dell XPS via USB -C or is it only compatible with the USB-C on a Macbook/Mac?)

No, the Apple Thunderbolt 3 to Thunderbolt 2 Adapter is only for Thunderbolt devices.

You want a USB-C to Mini DisplayPort female adapter, or a USB-C to VGA adapter. The Plugable USBC-VGA adapter is superior to the Apple adapter because it can do up to 330 MHz allowing for higher resolutions and refresh rates.

• Answered by Joseph V from Fort Langley
• 12/05/2019
• Flag as inappropriate Answer (Can this be used with the Apple Mini DisplayPort to VGA adapter?)

The Thunderbolt 3 to Thunderbolt 2 adapter is only for connecting Thunderbolt 2 devices to Thunderbolt 3 computers, or for connecting Thunderbolt 3 devices to Thunderbolt 2 computers.

The LG 38UC99-W is not a Thunderbolt display.

The simplest way to connect the LG 38UC99-W to the MacBook Pro Retina 2015 is with a Mini DisplayPort to DisplayPort cable (not included). Connect the included USB Type A to C cable for USB functionality (to enable the two downstream USB 3.0 ports of the display).

Another option is to connect the display (with the included USB Type C cable) to one of the Thunderbolt 3 ports of a Thunderbolt 3 device that has two Thunderbolt 3 ports (such as a Thunderbolt 3 dock). Connect the Thunderbolt 3 device to the MacBook Pro Retina 2015 with the Apple Thunderbolt 3 to Thunderbolt 2 Adapter and a Thunderbolt 2 cable. This method is much more expensive, but gives you all the ports of the Thunderbolt 3 dock, and frees up the DisplayPort input of the display to be used with a different computer.

• Answered by Joseph V from Fort Langley
• 10/04/2019
• Flag as inappropriate Answer (Does this adapter + Thunderbolt Cable support connection to LG 38UC99-W USB-C port from MacBook Pro Retina 2015)

The Sabrent EC-NVME is a USB 3.1 gen 2 device so the max speed you could expect is a little over 900 MB/s which is a good portion of the theoretical limit of USB 3.1 gen 2 (9.7 Gbps considering the encoding overhead of 128b/132b but not the overhead of the USB protocol).

The best (only?) way to add USB 3.1 gen 2 to a Mac that only has Thunderbolt 2 is to connect a Thunderbolt 3 device that has two Thunderbolt 3 ports using an Apple Thunderbolt 3 to Thunderbolt 2 adapter. The second Thunderbolt 3 port of the Thunderbolt 3 device can be used for USB 3.1 gen 2 devices.

Some Thunderbolt 3 docks also have other USB 3.1 gen 2 USB-C ports. If they are based on the ASMedia ASM1142 (8 Gbps PCIe 2.0x2 or 7.9 Gbps PCIe 3.0x1), then you'll get slightly better performance using a Thunderbolt 3 port. I think they all use the ASM1142 because it only requires one PCIe 3.0 lane from the Thunderbolt 3 controller leaving three lanes for other controllers (usually two USB 3.0 controllers and one Ethernet controller but sometimes a FireWire or eSATA controller).

Check the Wire Cutter review "The Best Thunderbolt 3 Docks" for more info.

• Answered by Joseph V from Fort Langley
• 18/02/2019
• Flag as inappropriate Answer (how to connect Sabrent EC-NVME (with USB 3.1 Gen 2 USB Type-C) to Mac Pro (2016) (Model: MacPro6,1 6-Core Intel Xeon E5 3.5 GHz) thru THUNDERBOLT 2?)

The Thunderbolt 3 to Thunderbolt 2 adapter is for Thunderbolt devices only.

The Samsung Portable T5 2TB USB 3.1 SSD is a USB device. It comes with a USB-C to USB-A connector so you can connect it to one of the iMac's USB ports.

The iMac's USB ports are USB 3.0 allowing up to 5 Gb/s which might get you up to 430 MB/s from the T5.

To add USB 3.1 gen 2 (up to 10 Gb/s) to the iMac, you could use a Thunderbolt 3 dock attached to the iMac using the Thunderbolt 3 to Thunderbolt 2 adapter. You would connect the T5 to the second Thunderbolt 3 port of the Thunderbolt 3 dock which could allow you to get up to 540 MB/s from the T5.

A Thunderbolt 3 dock to get one USB 3.1 gen 2 port is not worth the expense.

Another option is a Thunderbolt 2 PCIe enclosure (or Thunderbolt 3 PCIe enclosure plus Thunderbolt 3 to Thunderbolt 2 adapter) with a USB 3.1 gen 2 PCIe card which would get you at least two USB 3.1 gen 2 ports. But that is still expensive.

• Answered by Joseph V from Fort Langley
• 30/09/2017
• Flag as inappropriate Answer (I'm looking to get a Samsung Portable T5 2TB USB 3.1 SSD and have an iMac with tb2 ports would this adapter work?)

If you mean the CJ79, then I think so.

Thunderbolt 2 supports DisplayPort 1.2. Thunderbolt 3 supports two DisplayPort signals but I think only one is used for 3440x1440@100Hz (30bit color) = 14.9 Gbps so Thunderbolt 2 should be sufficient and there should be remaining bandwidth available for the USB 2.0 ports.

Only the Apple Thunderbolt 3 to Thunderbolt 2 adapter allows connecting Thunderbolt 3 devices to Thunderbolt 2 computers so this is the adapter you need.

• Answered by Joseph V from Fort Langley
• 17/02/2019
• Flag as inappropriate Answer (mac pro to thunderbolt 3 display)

No, the iPad Pro 2018 does not have a Thunderbolt 3 port. You cannot connect a Thunderbolt dock to a USB-C port that does not support Thunderbolt unless the Thunderbolt dock uses the new Titan Ridge Thunderbolt 3 controller. The Belkin Thunderbolt 2 Dock uses an old Falcon Ridge Thunderbolt 2 controller.

The USB-C port of the iPad Pro 2018 supports USB 3.1 gen 2 and DisplayPort 1.4 but not Thunderbolt, so you will want to find a USB-C dock that supports USB 3.1 gen 2 and DisplayPort 1.4.

The HP Thunderbolt Dock G2 can be connected to either a Thunderbolt 3 port or a USB-C port because it uses the new Titan Ridge Thunderbolt 3 controller. You'll need to add a DisplayPort to HDMI 2.0 adapter for your display, and a Thunderbolt 3 to Thunderbolt 2 adapter for your MacBook Pro 2013.

Most Thunderbolt 3 docks use the older Alpine Ridge Thunderbolt 3 controller which cannot be connected to a USB-C port that does not support Thunderbolt. If the dock supports DisplayPort 1.4, then you can be sure that it uses the Titan Ridge Thunderbolt 3 controller.

You could settle for a USB-C dock that supports USB 3.0 and DisplayPort 1.2 or HDMI. You can connect a USB-C dock to a Thunderbolt 2 Mac using a Thunderbolt 3 device or dock that has two Thunderbolt 3 ports - the USB-C dock would connect to the second Thunderbolt 3 port of the Thunderbolt 3 device.

• Answered by Joseph V from Fort Langley
• 25/02/2019
• Flag as inappropriate Answer (Could I use this adapter to connect iPad Pro 2018 with a belkin TB2 dock? And to drive a monitor with hdmi of the dock?)