See Thread "UEFI BIOS Problem", below, for particulars on the (main) system.
I need instruction on how to set up the BIOS properly. The manual is about useless, I'm having USB problems on this board, seemingly no matter how I set it up. The board is a Gigabyte GA-Z77X-UD5H - Rev 1.1 with an Intel i7-3770 (not -K) CPU, and with everything running stock. "Optimized Defaults" is the starting point.
I'm trying to keep the system in "Legacy" - nonUEFI mode so I can boot into Linux occasionally. I think the problem is in how the xHCI and EHCI settings are configured, along with some other, unknown, factor, and I'm going more nuts. Safe Boot is disabled, also. I do have some USB3 peripherals, so I don't want to simply disable USB3 entirely.
The problem is that some of the USB2 ports and some of the USB3 ports are active during POST and Setup, but not all, and not always the same ones. ALL ports are up and active once the OS (Win 7 -64) gets loaded and running. The available ports depend on the state of the machine. During POST, when I want to get into setup, certain ports are available. If I boot to a USB stick (assuming I can find a port to do so with, and that allows me to enter the boot selection screen - not always a guarantee), or a DVDROM (different ports here too!), everything changes.
Could this possibly be related to the note I saw somewhere that suggested having several USB2 devices plugged in before installing Intel USB3 drivers? Maybe I got that wrong. I don't recall seeing WHICH ports needed to be occupied, just that some did.
Any assistance will be greatly appreciated.