Asus UEFI Boot Settings

[Sauntache]

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[zir_blazer]

Technically you're doing a UEFI booting. I suppose that Option ROMs like the one of your Video Card should be loaded in BIOS compatibility mode (My Radeon 5770 doesn't work if I use the "Legacy only" option).
Check this Thread, pay attention to the UEFI "SataDriver" because its related to the Intel RAID that you want.