I've got a ton of USB devices that are blowing past the resources limit of USB 2.0, so I desperately want to use the second Intel USB 3.10 eXtensible Host Controller - 1.20 (Microsoft) that shows up in Windows 10 Device Manager, but what physical connector(s) is attached to that second controller?
All the USB ports, front and back, including the USB C ports, all fall under the first Intel USB 3.10 eXtensible Host Controller - 1.20 (Microsoft).
Where is that second controller physical presence hiding? Is it the motherboard USB headers, though those are USB 2.0(?)
In the SOC implementation, per the Intel® 500 Series Chipset Family On-Package Platform Controller Hub Datasheet (Volume 1 of 2), "The PCH implements an xHCI USB 3.2 controller which provides support for up to 10 USB 2.0 signal pairs and 4 USB 3.2 signal pairs. The xHCI controller supports wake up from sleep states S1-S4. The xHCI controller supports up to 64 devices for a maximum number of 2048 Asynchronous endpoints (Control/Bulk) or maximum number of 128 Periodic endpoints (Interrupt/isochronous)."
This means there are four USB 3.2 ports and six USB 2.0 ports for the system design to work with. Three USB 2.0 ports are consumed by the design. This means you have available to you:
- three external USB 3.2 ports (two front panel and one rear panel).
- one internal USB 3.2 port (in M.2 2242 B-Keyed connector)
- one external USB 2.0 port (rear panel).
- two internal USB 2.0 ports (separate connectors).
Now, separate from the USB ports offered by the on-package PCH (and its xHCI controller), the SOC implements a separate xHCI controller that supports the USB-C subsystem. Two USB4-compliant USB-C/Thunderbolt 4 ports are provided on the back panel.
So, I think I have answered your question; the second xHCI controller, to the extent possible, is accessed via the two USB-C connectors.
Hope this helps,
Thank you for your helpful detail!
Interestingly, when a keyboard/mouse wireless adapter is plugged into any of the ports, it always shows up under the first controller, no matter which port it's plugged into.
When a USB 3.0 Hub is plugged into one of the C ports, it's Super Speed (virtual?) hub shows up under the second controller, confirming your info.
Unfortunately, and oddly, my USB 2.0 devices (plugged into the USB 3.0 Hub that's plugged into a C port) always show up under first controller, not the second USB C controller, which quickly becomes a limitation.
My USB 2.0 devices are combination devices that each use up multiple endpoints, hence the need to spread them out over multiple controllers to avoid this dreaded problem Windows USB Out of Resources error:
This device cannot start (Code 10)
Insufficient system resources exist to complete the API.
I'm desperately interested in anything that will overcome these limitations.
Thank you for the information provided.
I will proceed to check the issue internally and post back soon with more details.
Intel Customer Support Technician
I would like to bring this issue and discuss it with the Intel® NUC team for further investigation/clarification; however, it would be very useful to have some screenshots showing how the system is detecting the different devices, also a list of the devices you are connecting can help us with the research.
Intel Customer Support Technician
I hope you are doing fine.
I have not heard back from you. So I will close this thread. If you need any additional information, submit a new question, as this thread will no longer be monitored.
Intel Customer Support Technician.