Asus RS926-E7/RS8 - Manual (Page 177)

ASUS RS920-E7/RS8; RS926-E7/RS8 7-13
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>.