go into classic bios mode
enable UEFI and Legacy Boot.
if you disable legacy boot it get's stuck at 92 no keyboard, atleast with bios 0085 for me it did.
I do not have an answer for you but I will add that I tried flashing to 0091 [same board] and it was only partially successful. It still shows I have version 0085 but some things have changed - for instance the Intel Desktop Utilities will now run and they would not before.
I'm somewhat afraid to try and flash again. Not sure why there was a failure.
I have tried on two PCs now (see my first post) both have the DZ77BH-55K motherboard both will not reboot after the BIOS is updated. One PC took several attempts to recover the BIOS, I was worried it might not recover, I have never seen a board go as crazy on BIOS recovery as this one did!!!
I have also noticed that things changed in the BIOS even though both PCs are still showing the 0085 loaded, e.g. sleep now works OK, it didn't before attempting the update.
QUESTION: Are the BIOS defaults restored automatically when the BIOS is updated or are the USER settings kept? Does the BIOS when updating use the USER settings or use a set of default settings during the update process?
The answer to the above will affect the suggestion by Shaun as I can only get into the BIOS settings before I update. Once the update is installed neither PC gets past post, so I can't see the BIOS settings.
One issue I have (with 0085) is that both PCs try to to boot from my backup drive when it is connected to the rear panel USB 3.0 port. I get an error message that reads something like "unable to find active boot partition, press control/alt/delete". I have to either turn off the backup drive power each time I boot or turn off "Boot from USB" in the BIOS settings to stop it happening with the drive on and connected. WHY DOES IT DO THIS?
The board status LED (I) in post indicate "I, Hard Drive Initilization = off" when the BIOS update is in progress, i.e. after it has completed the flash and the PC is trying to boot and it gets stuck in post. Could it be that BIOS is looking for information on my "C" drive to do this but can't find it because it's looking at the wrong drive path. By the way I have removed the backup drive in the USB 3.0 port but no change, but it could still be looking in the wrong drive path.
THIS BOARD HAVE GIVEN ME THE WORST EXPERIENCE I HAVE EVER HAD TRYING TO UPDATE THE BIOS, EVEN WORSE THAN THE ALLTIME INTEL LEMON THE DG45ID.