When entering the boot menu (F8) on boot, I can't see devices in my USB 3 slots. As soon as I move the thumb drive to the USB 2 slots it boots fine.
Thumb drive is a SanDisk Extreme 64gb USB 3.0 running Ubuntu 14. (though this is irrelevant as no USB's are recognized from boot menu or in bios when in the USB 3 slots).
USB 3 is turned on in bios, and within windows the USB 3 slots function perfectly at USB 3 speeds.
I just updated the bios to the latest version, but still no luck. Motherboard is an Asus p6x58d-e.