Asus P9D-E/4L - Manual (Page 71)

4-6 Chapter 4: BIOS setup
The utility verifies the file, then starts updating the BIOS file.
DO NOT shut down or reset the system while updating the BIOS to prevent system boot
failure!
The utility returns to the DOS prompt after the BIOS update process is
completed.
4. Reboot the system from the hard disk drive.
The BIOS update is finished! Please restart your system.
C:\>
ASUSTek BIOS Update for DOS V1.06 (09/08/04)
Current ROM Update ROM
Note
Writing BIOS:
FLASH TYPE: MXIC 25L1605A
PATH:
BOARD: P9D-E/4L
VER: 0201
DATE: 12/01/2013
BOARD: P9D-E/4L
VER: 0202
DATE: 12/09/2013
WARNING! Do not turn off power during flash BIOS