Hi,
there's a bug in the last version (1.70) of extreme6's bios: when the system is OFF (or hybernated) I used to charge my G700 mouse by attacching it to the usb cable, but with 1.70 bios, even the usb power is OFF and so the mouse will not charge...
Back to normal with 1.60 version

This issue was tested on 2 different z77-extreme6...