Asus Z9NA-D6 - Manual (Page 163)

ASUS Z9NA-D6 6-15
4. Use the USB drive to provide the third-party driver during the OS installation.
Type the command brokenmodules=ahci in Boot Options field, and press
<Enter>.
5. When below screen appears, select the USB floppy disk drive (sda) as the
driver update medium. Select OK, then press <Enter>.
Please choose the Driver Update medium.
OK Back
sda: USB Floppy
Other device
6. Select Back and follow the onscreen instructions to finish the installation.