Howto Flash your BIOS the quick and dirty way

I never really understood why you should always get a bootdisc environment for flashing your motherboard bios. Flashing a bios takes few seconds including the verification of the written data. Why should a stable system fail right in this moment? Yeah this could fuck the whole system up but who tells you you got a secure power supply in case you use a bootable environment from a CDROM? So I went another way. Without creating a bootable cd. So…

What to do

  1. Flashing your BIOS is dangerous. You do anything at your own risk. Don’t flash your bios if everything works or you don’t know what you’re actually doing.
  2. Obtain flashrom (apt-get install flashrom)
  3. Check if your motherboard is supported. (chances are good)
    sudo -s
    flashrom -L
  4. Obtain the right (the one for your motherboard) bios image from your vendor
  5. If you made important modifications in your bios settings (overclock?) write them down. All your settings (including saved ones) will probably disappear with the update)
  6. IF you’re completely sure you got the right bios image for updating AND you made sure flashrom is about to update your motherboard bios and not sth else OTHERWISE check below
    sudo -s
    flashrom -w yourimage

    Check the programs output. Don’t reboot if it tells you sth went wrong badly!

  7. If everything worked. Reboot and reconfigure your bios settings.

How do I know I got the right image and flashrom will flash the motherboard bios?

  1. Obtain the current bios of your motherboard.
    sudo -s
    flashrom -r readbios
  2. If you know or you are able to guess your bios version obtain the outdated version you currently use from your vendor too.
  3. Check wether all images have the same size.
  4. Obtain vbindiff (apt-get install vbindiff) and check the hexdata DON’T EDIT ANYTHING
    vbindiff readbios unmodified_outdated_same_v_from_vendor

    If there’s a lot (!) different this is not your bios. (Some differences occour because all your settings probably are saved there too.) To see “a lot” compare your bios with the one you want to replace it with (the new). There should be much more difference.

    vbindiff readbios newbios

    My biosimages all have a date at the end which I could see in the hexeditor. If you have that too, check it! The bios you read from your motherboard and the outdated from your vendor should have the same date. The new image should have a newer date at exactly the same place.

  5. So if the filesize does not differ, you got a date in your hexfile and you’ve read Nr. 4 carefully you should have the right bios and flashrom should write it to the right flashmemory (the one of your motherboard).