9 Replies Latest reply on Aug 11, 2016 6:37 PM by cvare

    NUC5CPYH xhci controller


      Hi, I have a nuc NUC5CPYH and I need to disable the xhci feature.

      However this option is not present in the BIOS, my current BIOS version is 0043.

      There is a BIOS release with that option?

      Or how can I disbale the xhci mode?


      Thank you

        • 1. Re: NUC5CPYH xhci controller

          Hello, lucak:


          This feature is not available for this NUC model, it is not preset in the BIOS versions for this NUC. Is there any particular reason that you want to disable this feature?



          • 2. Re: NUC5CPYH xhci controller


            I need to connect a lot of devices (ex. 300 Android tablet) to the NUC in order to perform sequential operations (like install an application).

            Now, I have a 4 port PCI Express SuperSpeed 3.0 with dedicated channels, I wanted to connect this card via the half-size Mini PCIe on the NUC

            and be able to connect more than 300 devices.

            With the XHCI controller it seems not possible because it has a limitation (the max number of devices the XHCI supports is 32 with UBUNTU), so i wanted to use the ehci controller instead

            which supports 127 devices per port, enabling a maximum of 508 connected USB peripherals with my 4 port expansion card.

            Do you have some advise for me?

            Thank you

            • 3. Re: NUC5CPYH xhci controller

              In this specific NUC model this feature is not available.

              If you disable the xHCI from any platform you will be disabling the capability of the SuperSpeed 3.0, it won't enable support for more or less USB ports. The capability of supporting more or less ports is a combination between the processor and chipset, meaning that these two have to have this support. Based on that, you should be looking for servers systems, I do not have an specific system configuration but server motherboards and processors should provide what you are looking for.


              • 4. Re: NUC5CPYH xhci controller

                Ok thank you,

                however, I just need to connect more devices and the Xhci controller seems to have a lower limit

                on the number of devices. 

                Also in my pc, there is that limit with the xhci controller and when i disable the Xhci mode, i can support more than 32 devices.

                Which are the NUC devices that have the possibility to disabling the XHCI mode?


                Thank you,


                • 5. Re: NUC5CPYH xhci controller

                  I have checked and these have the xHCI; Intel® NUC Kit NUC5i3RYH, Intel® NUC Kit NUC5i3RYK, Intel® NUC Kit NUC5i5RYH, Intel® NUC Kit NUC5i5RYK and Intel® NUC Kit NUC5i7RYH.



                  • 6. Re: NUC5CPYH xhci controller



                    I have exactly the same problem, and as I see in the thread below, Intel developpers have add the disable XHCI button on the last BIOS:

                    NUC 340101wyk unable to use the USB 2.0 controller.  Need to set USB to eHCI

                    Is it possible to add it for the NUC5CPYH ?

                    Many thanks

                    • 7. Re: NUC5CPYH xhci controller

                      intel ?  i buy 3 x nuc5cpyh , and install ubuntu , i use ft232 usb to uart on nuc , very unstable.

                      i ask ubuntu forum , somebody tell me need disable xhci on bios , but i cant find out any xhci option.

                      ok , i check intel forum , intel tell me Intel® NUC Kit NUC5i3RYH, Intel® NUC Kit NUC5i3RYK, Intel® NUC Kit NUC5i5RYH, Intel® NUC Kit NUC5i5RYK and Intel® NUC Kit NUC5i7RYH  this support disable xhci .

                      I contacted my Tmall mall, return or replacement, tmall tell me , the quality is no problem, can not be returned.

                      It feels like eating ****.

                      • 8. Re: NUC5CPYH xhci controller

                        Hi All,


                        XHCI cannot be disabled on this unit, the SOC does support both USB 2 and USB 3, but USB 2 uses EHCI, USB 3 uses XHCI solely, and XHCI cannot downgrade to support EHCI on USB 3 port.

                        I guess the recommendation would be to find a driver that supports XHCI.



                        Ronny G

                        • 9. Re: NUC5CPYH xhci controller

                          Thanks Ronny. 


                          To be a little more specific, the SoC does NOT support EHCI, ONLY XHCI-which is backwards compatible to USB 2.  As Ronny said, you will have to find a driver that supports XHCI.


                          I really am sorry that you saw EHCI was supported.  If you can help me find where you saw that, we can fix that.