how to disable xHCI mode?

[uskysam]

Hi ,

My Desktop pc product is  HP prodesk 600 G2 sff.

I want to disable XHCI mode,like below

XHCI Mode = Disabled - The on-board USB 3.0 port function like a 2.0 port

but,i can't find this option in BIOS.

how cat i set iit up

thank you.

[DGroves]

usb 3.0 xHCI support is through the usb driver and canot be disabled

the usb 3.0 is backward compatable to usb 2.0 and usb 1.0

the usb 3.0 driver will auto detect the capabilities of the device it is talking to and auto switch to the required speed

IE- if a 2.0 device then it will downgrade the speed/protocall to 2.0 if 1.0, again it will do the same

newer systems using the later usb 3.0 chipsets can auto up/downgrade the speeds to each device attached to the usb 3.0 port IE_ you can have a mix of 2.0/3.0/1.0 devices attached and the usb 3.0 port will talk to each device at the required speed

in short there is no valid reasion to do what you are asking,.....so why do you want to do this?

[uskysam]

Thank you  very much.

Why do I have to do this ,because I have a VOIP  analogy voice card.
If used on usb 3.0, there will be problems that cannot be read data, causing sound interruption,if i can adjust the xchi option, can avoid this problem.

[DGroves]

and what voip card model do you have, and does the maker explicly state that it's not compatable with usb 3.0 xHCI is a part of the  3.0 usb spec.

also since most systems come with BOTH usb 3.0 and 2.0 ports why not use a usb 2.0 port.

[uskysam]

After testing, no matter whether you use usb 2.0 or usb 3.0, it will still be unreadable.
Similar results on other motherboards unless xhci mode is turned off.

So, why should I turn off the xhci mode.

[DGroves]

sounds like the usb device you are attaching has buggy usb firmware or the usb driver for the device is buggy

are you by chance trying  to install (or have installed) a usb device driver under compatability mode?