Thunderbolt / eGPU on Copano

This is a followup to my Linux thread where I was trying to get my ADLINK Pocket AI A500 eGPU working on a Copano chromebook. I figured it would be more appropriate to post in the Windows forum now that I’m trying this on Windows.

I followed Coolstar’s Windows guide and installed all of the necessary drivers, including purchasing and licensing the Thunderbolt drivers. I also followed the README to disable the power saving item for “Intel USB 3.20 eXtensible Host Controller”. Although on my system, it says 3.10?

In addition, I do not seem to have “Intel(R) TypeC PCIe” listed in Device Manager. What category should it be in? My coreboot version is MrChromebox-4.22.2-5-g822782a1001. This chromebook supposedly supports Thunderbolt 4/USB4.

The following devices are present, and I clicked through each one and they all say device is working properly.

  1. Intel PMC
  2. Intel IOM (Tiger Lake)
  3. Intel USB-C Mux
  4. Chromebook EC Bus
  5. Chromebook USB-C PD Notification
  6. Chromebook EC USB-C

I connect my eGPU with external power, then plug in to the chromebook with a Thunderbolt cable. (I can’t connect the TB cable first before powering on, because the eGPU itself will show a red error indicator light and won’t respond.) At this point, I don’t see any new devices show up. Scanning for new hardware changes doesn’t show anything new either. I even tried to install the Nvidia drivers, but it does not detect an Nvidia GPU, and the installation aborts.

I do have some suspicion that this eGPU might not be compatible with an EC-based Thunderbolt device based on my previous thread. It has in the past worked with an Intel desktop with regular Thunderbolt 3 on both Ubuntu and Windows.


I’ve had similar issues with my Razer Core X Chroma eGPU — its also TB3 likes yours.

I was thinking about picking up the TH3P4G4 eGPU dock (found on ebay or aliexpress) as Coolstar has confirmed this working with Chromebooks and the TB4 drivers.

Thanks for giving another example! I personally would still want this particular eGPU to work because it’s very portable. Do we know if there’s still efforts on getting more devices to be supported with the TB4 driver?

Edit: I bought a Cable Matters Active Thunderbolt 3 cable from Amazon and unlike the TB4 cable I was using, this cable did cause Windows to detect something. With this Active TB3 cable, I do hear a sound and I get notification saying “Thunderbolt device functionality might be limited.” This happens about every other time I connect and disconnect the cable. Unfortunately, the eGPU itself still isn’t showing up.