I have an Asus Crosshair V Formula Z motherboard. Doesn't have a manual or disc, it was open box.
I have it up and running. It can see all 4 WD SATA hard drives in the RAID 10 array. But it gives the message that the boot settings are not correct. It has a Compatibility Support Module, and it says the settings don't fully support my boot device (the WD RAID 10 array).
The settings are Launch: CSM Auto, enabled, or disabled
Boot device control: UEFI and Legacy OpROM, Legacy OpROM only, or UEFI only
Boot from network devices: Legacy OpROM 1st, UEFI driver 1st, or Ignore
Boot from storage devices: Both, Legacy OpROM first, Both, UEFI first, Legacy OpROM first, UEFI driver first, or Ignore
Boot from PCIe/PCI Expansion Devices: Legavy OpROm first, or UEFI driver first
I notice that if I connect my two DVD burners to the 5th and 6th SATA ports, it apparently tries to boot from them.