I have a DQ67OW board. Some time back I installed a copy of CERN Centos 7 on its HD and subsequently reformatted the HD.
The problem I have is that CERN Centos has installed an entry in the Boot manager which is always first in the the list and which I cannot get rid off. This has the effect the machine now cannot boot any OSes I have installed unattended. I have to be present at boot time to press F10, scroll down to one of the other entries and boot those. Otherwise BIOS stops with, "A Bootable device has not been detected" etc. error.
See here https://www.mklab.rhul.ac.uk/~tom/DQ67OW for some BIOS screenshots. The first picture shows the Boot Manager screen with the unwanted entry selected. The other pictures show the Main BIOS tab and the Boot tab with Advanced and Normal Boot Menu Type selected. In both cases the problem remains. I did find that disabling "UEFI Boot" on the Boot tab does actually make the "CERN Centos" boot entry disappear from that menu but an unattended boot fails as with it enabled. Moreover re-enabling UEFI Boot makes it come back, suggesting disabling UEFI Boot did not really make it go away.
I have tried all the other things I can think off in the Boot tab. None helped. I have updated the BIOS to the latest version using the IFLASH2.EXE utility in SWQ6710H.86A.0070.BI.zip, including with its /f and /md options. I also tried removing the coil cell and unplugging the PC from the mains for some time. Nothing helped.
After unplugging all SATA and USB devices from the board, the CERN Centos entry remains, demonstrating that Boot Manager entry has somehow been written into the BIOS!
Under Linux I dumped the BIOS settings using the dmidecode utility. Its O/P, should it be relevant is here http://www.mklab.rhul.ac.uk/~tom/DQ67OW/dmidecode.txt.
I am out of ideas and don't want to have to throw this board away.
create system restore point for security purposes
there is third party software will help you name EASYBCD 2.4, download from below site
You dont need to worry , because I have used same to 10 computers, install and run as administrator , click ok , ok , then
click on edit boot menu , on rightside , click on unwanted boot entries
disable uefi mode or secure boot , then boot as normal
then type system configuration In search box , click on system configuration , then click on boot tab , click on unwanted entry then delete, ok ok .
restart the windows
Boot back to your DOS image and redo the BIOS install using the following command line: "iflash2 /p xxxxx.bio /c /md /f", where xxxxx.bio is the name of the .BIO file you are installing.