ASROCK Z77 Extreme6 User Manual page 74

®
We recommend to use Intel Z77 SATA ports (SATA3_0,
SATA3_1, SATA2_2, SATA2_3, SATA2_4 and SATA2_5) for
your bootable devices. This will minimum your boot time and
get the best performance. But if you still want to boot from
ASMedia SATA3 controller, you can still enable this in UEFI.
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