Asus Maximus III Extreme - Manual (Page 110)

3-26 Chapter 3: BIOS setup
Marvell 9123 Controller [IDE Mode]
[Disabled] Disables the Marvell 9123 controller.
[IDE Mode] Set to [IDE Mode] when you want to use the Serial ATA hard disk
drives as Parallel ATA physical storage devices.
[AHCI Mode] Set to [AHCI] when you want the SATA hard disk drives to use the
AHCI (Advabced Host Controller Interface). The AHCI allows the
onboard storage driver to enable advanced Serial ATA features that
increases storage performance on random workloads by allowing
the drive to internally optimize the order of commands.
Marvell 9123 Boot ROM [Auto]
This item appears only when you enable the previous item(s).
[Enabled] Enables Marvell 9123 Boot ROM.
[Disabled] Disables Marvell 9123 Boot ROM.
[Auto]
Onboard USB 3.0 Controller [Enabled]
[Enabled] Enables the onboard USB 3.0 Controller.
[Disabled] Disables the controller.