Promise Pegasus 3 r4 Thunderbolt 3 to 2 adapter

  • Last Post 29 July 2019
IT DEPARTMENT posted this 16 July 2019

Hi there.  We have a Promise Pegasus 3 r4 and need to connect it to an older Mac with a Thunderbolt 2 port.


Can't seem to find a Thunderbolt 2 (male) to Thunderbolt 3 (female) adapter.


Can you please point us to one?



Order By: Standard | Latest | Votes
PROMISE Technology Inc. posted this 17 July 2019

Hi IT Department,

Apple sells a Thunderbol2 to Thunderbolt3 adapter.

  • As a bidirectional adapter, it can also connect new Thunderbolt 3 devices to a Mac with a Thunderbolt or Thunderbolt 2 port and macOS Sierra or later. 

IT DEPARTMENT posted this 17 July 2019

Thank you for the reply. We have a pair of these adapters in-house and have tried them to no avail. I checked the Pegasus 3 r4 Quick Start Guide and the following is noted before Step 1.

"The Pegasus3 can only be used with client devices equipped with a Thunderbolt 3 port. It CANNOT be connected to a Thunderbolt 2 or Thunderbolt 1 port."

The Mac that we're using has Thunderbolt 2 ports and is running macOS Sierra. We've connected the Pegasus3 units to it using the Thunderbolt adapters, and while the Thunderbolt 3 Link LED is illuminated, the Mac isn't seeing it. Should we be able to use this setup?

PROMISE Technology Inc. posted this 17 July 2019


It is also necessary to install the Pegasus 3 driver. It is available from the support page.

You can navigate to Pegasus > Pegasus 3 R4 > Driver, or download it from the link below.

Please note that this driver is for Mac OS X 10.12 or above.

Unless I am greatly mistaken, 10.12 is Sierra.

As an added note, you might want to download the Pegasus Utility to manage the Pegasus. 

ajttanbc Tan posted this 28 July 2019



I have PROMISE R4 12TB RAID System and now having problem for power on the system.

Just bought Feb 2019 

ajttanbc Tan posted this 28 July 2019



My PROMISE R4 12TB RAID system total no power. The unit have no lights to show the power on.

The fan not functioning. I used Windows 10 OS.

 The adaptor and cable used original from the packaging provided.


Please help.. 



ajttanbc Tan posted this 29 July 2019


Any service centre in Singapore for no power issues ?


Please advise.