topic Re:Thunderbolt compatibility TB4 to TB2 in Thunderbolt™ Share

Thunderbolt compatibility TB4 to TB2

Bassking — Wed, 26 Nov 2025 17:30:37 GMT

Hi Intel-community,
I've just bought an ASRock Board with the Z890 Chipset. This has TB4 connectors, but my external soundcard has a TB2-connector. I've tried my "old" TB3-TB2-adapter (from Apple), which used to work on my old TB3-Board, but this connection on my new TB4 board isn't even recognised. Yes, TB is enabled in BIOS. It seems to be, that TB4 is NOT downwards compatible to TB2, is that correct? And how do I make it work? It would be a terrible flaw in the TB-universe, if the downward-compatibility would end at TB3, rendering millions of external drives, monitors, docks etc. useless for no reason: on Mac TB4 is compatible all through TB1...
Any help here would be greatly apreciated, thanks!

Re:Thunderbolt compatibility TB4 to TB2

KennethB_Intel — Thu, 27 Nov 2025 04:55:18 GMT

Hello Bassking,

Thank you for reaching out to the Intel Community Forum. I understand your concern regarding the compatibility between Thunderbolt 4 and Thunderbolt 2 devices.

To assist you better, could you please provide the following details:

Have you updated the Thunderbolt drivers and firmware to the latest version?
Does the adapter work with any other TB4 device, or is it only failing with the soundcard?
Can you confirm if the external soundcard works when connected to another system using the same adapter?
Could you please provide us the SSU logs of your system? You can find instructions on How to get the Intel® System Support Utility Logs on Windows*

These details will help us determine whether the issue is related to compatibility, configuration, or hardware limitations. Once we have this information, we can guide you with the next steps.

We will wait for your response so we can further assist you.

Best regards,

Kenneth B.

Intel Customer Support Technician

Re: Re:Thunderbolt compatibility TB4 to TB2

Bassking — Thu, 27 Nov 2025 06:31:11 GMT

Hi Kenneth,

thanks for the fast reply. I don't have a different TB4-board or other TB4 devices to test the adapter, I'm afraid. But I know the adapter and the soundcard work perfectly on my "old" board, an ASRock Z97M Pro4. This only had a TB-header on the board and needed the expansion card "Thunderbolt 3 EX" from ASRock. This worked perfectly and was disconnected in a fully working condition. The soundcard also works when connected to the computer via USB 2, but I prefer TB for lower latency. The Computer is a new build with all the newest drivers and firmware on the board. The soundcard driver is installed. But my system doesn't see the TB-adapter. Attached is also my devices-screenshot where you can see that something is "wrong" with the USB4/TB-port if the adapter is plugged in. W/o the adapter it shoes the USB4/TB-port working normally.

Attached is my SSU-log.

Thanks for the help!

Best regards,

Max

Re:Thunderbolt compatibility TB4 to TB2

KennethB_Intel — Fri, 28 Nov 2025 03:30:27 GMT

Hello Bassking,

Thank you for your response. Please allow me some time to conduct a more thorough internal investigation to better understand the issue and identify the appropriate steps to take.

I will make sure to provide you with an update as soon as possible once I have more information to share.

Thank you.

Best regards,

Kenneth B.

Intel Customer Support Technician

Re: Thunderbolt compatibility TB4 to TB2

Bassking — Fri, 28 Nov 2025 06:15:34 GMT

Thanks Kenneth,

I hope we find a solution, as it would be very disappointing and not really understandable if the downward compatibility wasn't possible through the whole TB-line...

Greets

Max

Re:Thunderbolt compatibility TB4 to TB2

KennethB_Intel — Mon, 01 Dec 2025 03:31:57 GMT

Hello Bassking,

Thank you for your patience. Please see the details below regarding your request:

Thunderbolt 4 Backward Compatibility with Thunderbolt 2
Thunderbolt 4 does support backward compatibility with Thunderbolt 2, but it requires adapters and has some limitations:
- Compatibility Path:Thunderbolt 4 → Thunderbolt 3 (native compatibility)
- Thunderbolt 3 → Thunderbolt 2 (via Apple Thunderbolt 3 to Thunderbolt 2 adapter)
- Key Points:Adapter Required: Please check which adapter is most compatible with your motherboard.
Limitations:
- Compatibility is not guaranteed for all Thunderbolt 2 peripherals, especially older or specialized equipment.
While backward compatibility exists through adapters, it is not seamless and may require testing with your specific devices to ensure proper functionality.

Workaround for Connecting TB2 Devices to TB4 Ports

Please note this is only a workaround and not an official Intel statement:
TB2 audio interfaces often work but may need driver updates.
Check manufacturer websites for TB3/TB4 compatibility updates.

Clarification on Limitations

The limitations are due to multiple factors:

Hardware: Creates the fundamental incompatibility requiring active conversion.

Firmware: Handles protocol translation but introduces latency and compatibility gaps.

Adapter Quality: Determines how well the conversion is executed.

The most critical factor is hardware differences in electrical signaling and controller architecture, with firmware protocol translation being secondary.

Recommendations:

Since you are using an older version of Thunderbolt, an upgrade may be required. Please check with your motherboard manufacturer for compatibility and support options.

If you have further questions or need assistance, feel free to reply to this email.

Best regards,

Kenneth B.

Intel Customer Support Technician

Re: Re:Thunderbolt compatibility TB4 to TB2

Bassking — Tue, 02 Dec 2025 20:06:35 GMT

Hi Kenneth,

thanks for the reply, that is what I have found out already, but it doesn't solve my problem. I have been in touch with ASRock and with MOTU (the manufacturers of my Moboard and the soundcard), and both state that this is definitely an Intel-related problem, as it must be the chipset drivers for Windows that are blocking the compatibility. It seems (forums say so, too), that there was an update for Chipsets a while back (might be a year or so ago), when the backward compatibility for Windows PCs was suddenly dropped. On Mac there is no problem, TB4 is fully backward compatible through TB1 - with an adapter, the TB3-TB2-adapter works fine here. As the chipsets are almost all Intel for both Operating Systems one might ask what has led Intel to render so many TB2 and TB1 externals useless - but only for Windows-users.
So now I have a few questions:
Can you confirm whether it is true that Intel uses a different approach to supporting Mac and Win regarding the TB compatibility?

Why was this obvious and unnecessary crack in continuity of TB made only for Windows?

As this is a very important subject and TB is a growing platform - could Intel PLEASE fix this in one of the next firmware or BIOS updates?

Please answer these questions, I know quite a few people out there are desperate for an answer.

Thanks a lot
Max

Re:Thunderbolt compatibility TB4 to TB2

KennethB_Intel — Wed, 03 Dec 2025 00:50:19 GMT

Hello Bassking,

In order for me to provide you with an accurate answer, please allow me to coordinate this first with the team.

I'll get back to you as soon as possible.

Thank you!

Best regards,

Kenneth B.

Intel Customer Support Technician

Re:Thunderbolt compatibility TB4 to TB2

KennethB_Intel — Wed, 03 Dec 2025 04:48:00 GMT

Hello Bassking,

Thank you for your patience. While Intel manufactures the component, the integration into the system is handled by the Original Equipment Manufacturer (OEM).

As we have limited information regarding the specific implementation, I recommend contacting ASRock Support for further assistance. They will have the most accurate details and resources to help resolve your concern.

Since there is no further action required on our end as of this time, I will now proceed to close this case. If you require further assistance, please feel free to submit a new inquiry, as this thread will no longer be monitored.

Thank you!

Best regards,

Kenneth B.

Intel Customer Support Technician