Asus X99-E WS/USB 3.1 Manual page 139

Booting the system in DOS environment
To boot the system in DOS:
1. Insert the USB flash drive with the latest BIOS file and BIOS Updater to the USB port.
2. Boot your computer then press <F8> to launch the select boot device screen.
3. When the select boot device screen appears, insert the Support DVD into the optical
drive then select the optical drive as the boot device.
E1:
USB DISK 2.0 (3824MB)
UEFI: (FAT)
Enter Setup
4. When the booting message appears, press <Enter> within five (5) seconds to enter
FreeDOS prompt.
ISOLINUX 3.20 2006-08-26 Copyright (C) 1994-2005 H. Peter Anvin
A Bootable DVD/CD is detected. Press ENTER to boot from the DVD/CD.
If no key is pressed within 5 seconds, the system will boot next priority
device automatically. boot:
5. On the FreeDOS prompt, type d: then press <Enter> to switch the disk from Drive C
(optical drive) to Drive D (USB flash drive).
Welcome to FreeDOS (http://www.freedos.org)!
C:/> d:
D:/>
Updating the BIOS file
To update the BIOS file:
1. On the FreeDOS prompt, type bupdater /pc /g and press <Enter>.
D:/> bupdater /pc /g
ASUS X99-E WS/USB 3.1
E13611_X99-E_WS_USB31_UM_V4.indb 67
Please select boot device:
ASUS DVD-E818A6T
USB DISK 2.0 (3824MB)
 and  to move selection
ENTER to select boot device
ESC to boot using defaults
(4069MB)
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