What's new
  • Please do not post any links until you have 3 posts as they will automatically be rejected to prevent SPAM. Many words are also blocked due to being used in SPAM Messages. Thanks!

ASRock Z270 Supercarrier - blackscreen 09/d0, how to switch to backup BIOS?

kartik_subbarao

New member
Joined
Feb 22, 2017
Messages
2
I have an ASRock Z270 Supercarrier and used the Internet Flash utility in UEFI setup to upgrade the BIOS from 1.10 to 1.11. The upgrade process completed successfully and no errors were reported. However, when the computer rebooted with the new BIOS, it just hung with a blackscreen. I have rebooted the system over 20 times, with the same result. The boot process runs for about 15 seconds, the Dr. Debug LED settles on 09 or d0, and remains in that hung state.

According to the manual, "after several failed boot attempts, the backup BIOS will take over" -- but this doesn't seem to be happening. It still boots from the active BIOS (BIOS_A_LED is on). I also tried unplugging the computer and depressing the clear CMOS button for over 10 seconds, but that didn't seem to have any affect.

Is there any way that I can force a switch to BIOS B, or alternatively, downgrade BIOS A back to 1.10? The motherboard was working fine with 1.10 before I upgraded it to 1.11.
 

Vittra

Well-known member
Joined
Oct 30, 2009
Messages
1,097
Location
Ontario
Try this:

1) Turn off computer
2) Disconnect power cord from PSU
3) Remove the CMOS battery for 15 seconds, then put back in.

You can then reconnect the cord and turn the computer on. I have found that the clear CMOS button does not always successfully clear all settings as it should.

It looks like the battery is underneath the first slot, so you might have to remove your GPU to get to it.
 

kartik_subbarao

New member
Joined
Feb 22, 2017
Messages
2
Problem solved

Good news -- I removed all but one of my RAM cards and was able to boot up with BIOS A. I attached a FAT32 USB stick with the 1.10 BIOS file and used the UEFI Instant Flash tool to successfully downgrade BIOS A. I then added back my other RAM cards and successfully booted the system just like it was before. Problem solved!
 
Last edited:
Error 403 Daily Limit Exceeded. The quota will be reset at midnight Pacific Time (PT). You may monitor your quota usage and adjust limits in the API Console: https://console.developers.google.com/apis/api/youtube.googleapis.com/quotas?project=345236864347 : dailyLimitExceeded

Latest posts

Twitter

Top