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USB 3.0 on Gigabyte UEFI Motherboards- XHCI Mode Explained

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Gigabyte Z77X-UD5H
CPU
i7-3770K @4.2-4.4GHz
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GTX 660 Ti
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As you may or may not know, Gigabyte has a setting in the BIOS called xHCI mode.
It can be set to Smart Auto, Auto, Enabled and Disabled.

Disabled turns off USB 3.0 entirely and makes all the ports USB 2.0.

The other three operate slightly differently, especially with regards
to OS X and as you can see from my screen shots, it appears that the
Auto mode is the one to pick for OS X. It's the only mode that allows the OS to see the VIA USB 3.0 hubs for example an it appears to show more information about USB 3.0 devices.

I'm not sure the performance is quite there, as there's no performance benefit using either mode, but in Smart Auto the devices don't even seem to show up.

Note: This only applies to the Z77, H77, B75 and Q77 boards with integrated Intel USB 3.0 ports. Also note that xHCI and EHCI Hand-off has to be enabled or the USB ports won't work at all.

Edit: Also note the "HS Port Switchable" settings. On the Z77X-UD5H there are four of these and they enable you to manually set your USB 3.0 ports to USB 2.0 mode if you chose disable rather than enable. This is handy for example during installation if you don't have additinal USB 2.0 ports on your case or via a bracket.
 

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Good explanation very helpful :thumbup:
 
Lion 10.7.4 on GA-X79-UD3/i7-3930K with XHCI enabled and EHCI disabled gives me no USB 3.0 ports at all. I only have enabled/disabled. How could I fix it? :?:
 
crops said:
Lion 10.7.4 on GA-X79-UD3/i7-3930K with XHCI enabled and EHCI disabled gives me no USB 3.0 ports at all. I only have enabled/disabled. How could I fix it? :?:

I should've been more clear, this doesn't apply to X79 boards and you need to have xHCI and EHCI enabled in OS X, or the USB ports won't work at all.
 
XHCI Mode = Disabled
The on-board USB 3.0 port function like a 2.0 port

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

XHCI Mode = Auto
The on-board USB 3.0 port function like a 2.0 port before OS USB 3.0 driver load.
If you reboot the OS, the on-board USB 3.0 port again function like a 2.0 port during this reboot BIOS phase before OS USB 3.0 driver load.

XHCI Mode = Smart Auto
The on-board USB 3.0 port function like a 2.0 port before OS USB 3.0 driver load.
If you reboot the OS, during this reboot BIOS phase, BIOS is "Smart" enough to avoid downgrade the USB 3.0 port back to 2.0 functionality before OS USB 3.0 driver load. So Smart Auto is faster than Auto on 2nd boot onward, but Enabled is fastest once you are sure the OS has the USB 3.0 driver installed, because it avoid the switching. Making the on-board USB 3.0 port function like a 2.0 port is mainly to support OS installation or to support OS that does not have build-in USB 3.0 driver, so that the USB keyboard would still work if the user plug-in a USB keyboard or any other USB devices into the USB 3.0 ports before the OS is installed with the USB 3.0 driver come with the motherboard.
 
thelostswede said:
As you may or may not know, Gigabyte has a setting in the BIOS called xHCI mode.
It can be set to Smart Auto, Auto, Enabled and Disabled.

Disabled turns off USB 3.0 entirely and makes all the ports USB 2.0.

The other three operate slightly differently, especially with regards
to OS X and as you can see from my screen shots, it appears that the
Auto mode is the one to pick for OS X. It's the only mode that allows the OS to see the VIA USB 3.0 hubs for example an it appears to show more information about USB 3.0 devices.

I'm not sure the performance is quite there, as there's no performance benefit using either mode, but in Smart Auto the devices don't even seem to show up.

Note: This only applies to the Z77, H77, B75 and Q77 boards with integrated Intel USB 3.0 ports. Also note that xHCI and EHCI Hand-off has to be enabled or the USB ports won't work at all.

Thank you for the Info, but does anybody know what solution works with my Motherboard? I would be immensly thankful for any info on that.
My Hackintosh is running really well with Lion except that the USB 3.0 ports dont work.

Thanks in advance.
 
That's kind of off topic, but have you tried the Renesas/NEC kext in Multibeast? It seems to be working with the Etron controllers, but there's no guarantee.

killerqueen44 said:
Thank you for the Info, but does anybody know what solution works with my Motherboard? I would be immensly thankful for any info on that.
My Hackintosh is running really well with Lion except that the USB 3.0 ports dont work.

Thanks in advance.
 
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