4. BIOS Update failed?

First aid

4. BIOS Update failed? - First aid

PC do not start after BIOS-Update? Blank screen and nothing happens?

With a little luck not all is lost. Because there are some methods for reactivating your PC. Depending on the method, we would need again a bootable DOS media, from which we will try to make a blind BIOS update. If the update process starts, it may be that (depending on the flashtool and BIOS vendor) different beeps are heard. So don't panic and wait a few minutes longer to make sure that the update process was terminated.

Note: the BIOS manufacturer AWARD have been taken over in 1998 by his competitor PHOENIX. So do not be surprised if you find both company names together on the BIOS setup screen.

  • CMOS-Reset:
    You should always reset the CMOS after updating the BIOS, because your old BIOS settings could not work together with your new BIOS version. The exact procedure should be found in the mainboard manual!
  • Dualbios (Mainboard with 2 BIOS-Chips):
    Mainboards with DualBIOS have two BIOS-Chips. One is the regular chip called MAIN-BIOS, and the other is the BACKUP-BIOS containing an intact copy of the original BIOS. Depending on the BIOS and mainboard manufacturer, there could be various methods to reactivate the MAIN-BIOS-Chip:
    • The BACKUP-BIOS takes automatically control after the next reboot and copies his chip data content onto the MAIN-BIOS-Chip.
    • Setting a special jumper on the mainboard.
    • A special keystroke during the boot process.
    Take a look into the mainboard manual how to reactivate a Dualbios.
  • Driver-CD with integrated BIOS update file:
    Some mainboard manufacturers such as ASUS enclosing a driver CD to any sold mainboard (in the original box), which contains a BIOS update file. So you can boot your PC from this CD and have to wait ~ 5 minutes.
  • Intact BIOS-Boot-Block:
    Every BIOS-Chip contains a special data area, the so-called BIOS-Boot-Block. This BIOS-Boot-Block ensures that a PC can start the boot process, and checks, what is important in our case, if a bootable DOS media (USB flash drive, CD, floppy disk) is present. If the BIOS-Boot-Block detects a bootable DOS media, he tries to boot it and restarts a new BIOS update.

    Due to the fact that the monitor screen is black, we cannot make any keystroke. But it is possible to create a so-called DOS batch file. The batch file can contain multiple lines of commands, with line-by-line, from top to bottom, a special command can be executed. Even better: it can start automatically when you rename the batch file to: autoexec.bat.

    • Create a text file and rename it to autoexec.bat.
    • Insert your update command into the autoexec.bat (see Start the BIOS-Update).
    • Copy the autoexec.bat and also your flashtool and the BIOS file onto a bootable DOS media (USB flash drive, CD, floppy disk) .
    • Boot the DOS media.
    • Wait at least 5 minutes before you restart your PC!

    So what happens? The bootable media starts DOS. Then DOS starts the autoexec.bat, and this batch file executes each command line-by-line, inclusive your BIOS update command.
    • Create the text file autoexec.bat, which contains only the following 1 single line:
      awdflash.exe updatefilename /py /sn
      (don't forget to rename these example filenames with the real filenames of your flashtool and the BIOS file!)
    • Copy the autoexec.bat and also your flashtool and the BIOS file onto a bootable DOS media (USB flash drive, CD, floppy disk).
    • Boot the DOS media.
    • Wait at least 5 minutes before you restart your PC!
    • We need an empty and formatted Diskette.
    • Rename your BIOS file to amiboot.rom and copy it onto the Diskette.
    • Start the PC and press the keys "<Ctrl><Home>" until you can hear a beep tone.
    • Release the keys and wait.
    • The monitor screen stays black.
    • After ~ 1 to 5 minutes you should hear 4 beep tones, which are indicating that your BIOS-Chip is reprogrammed.
    On very old mainboards with PHOENIX-BIOS there was often a jumper called "Recovery Mode". Activate the jumper and boot from the "Crisis Recovery Disk" (from your mainboard manufacturer).
    This really dangerous method is only for PC professionalists who knew about the risk of a short circuit, with the result of a damaged mainboard, and only works if you have a second, completely identical mainboard!

    • Boot the second intact PC from a bootable DOS media (USB flash drive, CD, floppy disk) which also contains your flashtool and the BIOS file.
    • If you can see the DOS-Prompt (A:\>), remove the intact BIOS-Chip while the PC is still running (CAUTION RISK OF SHORT CIRCUIT!) and insert the defective BIOS-Chip.
    • Start your BIOS update.
    • Shut down the PC and reexchange the BIOS-Chips.


No luck at all ?
the last chance is to buy a new BIOS-Chip, or to reprogram the old BIOS-Chip.



 1. Preparation - Create a safe environment for a BIOS-Update
 2. Choose BIOS-Update method - DOS, Windows or per BIOS-Setup?
 3. Start the BIOS-Update - Flash your BIOS chip
 4. BIOS Update failed? - First aid


Attention: this Howto describes only a BIOS update according to standard, how it should work on most mainboards with AMI-BIOS, AWARD-BIOS or PHOENIX-BIOS. I cannot guarentee that it will work on your PC and I assume no liability for any damages! Please read the README files from your Mainboard manufacturer or PC manufacturer.

User-Comments: 4. BIOS Update failed?
Brian 18.Jan.2017 13:14

Hi I tried flashing the modded BIOS with winphlash and phlash16. Error with the signature on both programs... I've never had issues with flashing BIOS. What am I doing wrong? I even tried to extract the BIOS update utility from Sony that updated me to the latest BIOS in the first place and I don't see the BIOS in the exe file to replace. Please help me and thanks again Brian

ssathish mech 24.Sep.2016 14:25

My laptop also failure (shut down) on updating my bios but now its not starting and there is no any response from laptop and when i press the power button. the power light just blink and turn off. how to rectify the please any one give me the solution

shqair 5.Apr.2016 10:45

Thank you for your quick reply, and again thank you for your devotion to customers. what I did is as follows: I connected a usb keyboard only- no mouse- and a floppy disk drive. in addition to the cpu, RAM, and VGA adapter and power supply. I had the bios ROM and the bios update utility on the Floppy disk, and added a command line to the autoexec.bat file to run the update utility and load the bios ROM automatically- as the screen is completely black. and switched on the poer. it took approx. 2 minutes utill finished. then, there was a reboot, and guess what?!! There is a bios post screen on the monitor! the motherboard was bios-flashed successfully!!!! and everything went fine after that. thanks again and again.

biosflash 29.Mar.2016 14:25

1. Try to reset the CMOS (10-Cent-Method):

2. No luck? Try this:

Please note: while testing, you should remove all unnecessary additional hardware components from your PC (not on Laptops)! You only need: 1 CPU, 1 RAM 1 Graphic adapter, Power supply unit + mainboard. No CD- and HDD drives! No USB-Sticks! No TV-, Sound-, and other Controller cards, etc.!
Connect USB Mouse and USB Keyboard only on USB2.0 ports! Don't use USB3.0!

Shqair 29.Mar.2016 11:25

Greetings, I have an MSI MS-7252 AMD AM2 Motherboard. I tried to flash the bios but failed. what I get is a completely black screen with nothing at all! but the MB beeps normally. I tried to recover, using the jumper, but got nothing changed. removed the battery and waited a whole night, still blank. MB detects NO-RAM and beeps, all beeps are normal, it simply does not display on screen. I also tried changing the RAM stick with many other sticks,,, still same result. Any chance for restoring my MB to life?

andy999 21.Sep.2015 13:23

Well, I guess that even with 20+ years of PC experience, you never stop learning!! Up to now, I was sure that a knackered BIOS will not even boot a floppy (remember, it stands for Basic I/O System). But now I learn that even with no video on the monitor, you can boot into DOS with a BIOS flash tool on the booting media! That's amazing.

biosflash 26.Jun.2015 15:26

Your utility EasyFlash confirms that your chip is defective. You could try to update the bios a 2nd time, but i think it fails again, or you will get a black screen.

msk 26.Jun.2015 15:14

@biosflash: Thank you for the quick reply! So, you're saying I should most probably have it replaced altogether? Is there a utility that I could use to confirm that it is defective, prior to replacing it?

biosflash 26.Jun.2015 15:04

It seems your bios chip is defective if the verification failed.

msk 26.Jun.2015 12:23

I updated my Asus K75 laptop BIOS using the flash utility within the BIOS itself (EasyFlash) and a USB stick. The update didn't go completely fine, because the verification failed (at the 100% point of the process), but the computer is booting properly and the BIOS status bar is showing that it is updated to the latest version. The only thing that is wrong is that when I choose to enable UEFI, the option disappears from the menu and doesn't come back (as Disabled again) until the next boot. What do I do, do I try flashing it again, do I reset the CMOS? Kinda clueless, and afraid that one of those would brick the mobo completely.

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