BIOS Boot-USB-Stick

Howto: BIOS-Update per bootable USB-Stick

BIOS Boot-USB-Stick - Howto: BIOS-Update per bootable USB-Stick


A guidance how to create a bootable USB-Stick / Pendrive (incl. MS-DOS system files) to perform a BIOS update.

see also: BIOS-Update Howto: step-by-step instruction
see also: BIOS Update per bootable CD
see also: BIOS Update per DOS-Boot-Diskette



  • OS: Windows XP, Vista, 7 and 8. The HP_USB_Disk_Storage_Format_Tool do not work under Windows 10!
  • The Laptop-/Mainboard-BIOS must support bootable USB-Sticks - which should apply to most of all modells which are not older than 4-5 years. If an USB-Stick was recognized during the boot process, the BIOS will integrate it as a removable drive, or as a normal drive.


The following tools are needed:

  • Ultimate BIOS-Boot-Edition:
    - usbdos (folder contains the 3 hidden! MS-DOS system files, io.sys and msdos.sys)
    - HP_USB_Disk_Storage_Format_Tool v2.2.3.exe (Hewlett-Packard's Format-Utility for USB-Sticks)
    DOWNLOAD Ultimate BIOS-Boot-Edition - 1.2MB
  • Flashtool - BIOS-Programming-Software (.EXE as file extension), which programs the BIOS file onto the BIOS-Chip, and the BIOS file. Both files must be downloaded:
    - Mainboard, bought in its original box: from the mainboard manufacturer website, or
    - Notebook or brand PC: from the notebook/brand PC manufacturer website.
    Both files must be specially designed for the DOS Operation system! If the manufacturer offers only files for Windows, you have to risk the BIOS update either directly under Windows, or you can re-program your old BIOS-Chip, or purchase a new, programmed BIOS-Chip.


New BIOS-Chips (incl. programming) --> in my Shop


Instruction to create a bootable USB-Stick

  • Open the Ultimate BIOS-Boot-Edition and the folder boot_usb_stick.
  • Copy the folder usbdos to your hard disk.
  • Start the HP USB Disk Storage Format Tool.
  • Select your USB-Stick under Device.
  • Choose FAT-32 under File system and activate the check mark Create a DOS startup disk.
  • Insert the path to your usbdos folder under using DOS system files located at:.
  • Press the Start button and wait until the tool has formatted the USB-Stick and has copied the 3 system files.
  • Rename the filename of your flashtool and the BIOS file, if they have more than 8 characters (not the file extension!).
  • Copy your flashtool and the BIOS file onto the USB-Stick.
The DOS system files are normally invisible, because their file attribute is set to hidden. If you would like to show these hidden files, you have to enable the option: "Windows-Explorer / Tools / Folder options / View / Show hidden files and folders" and to disable the option "Hide protected operating system files".


Starting the BIOS-Update from USB-Stick

  • First, go into your BIOS-Setup and change the Bootsequence to USB-Stick/Drive (search for an option like Bootsequence, First Boot Device, or something similarly).

  • Insert the USB-Stick and restart your PC. If all went well - MS-DOS starts and you can see the famous DOS-Prompt (C:\>).

  • Now you can start the BIOS update. Remember: it's a good idea to backup the old BIOS version.

  • See also: BIOS-Update Howto: step-by-step instruction

Happy flashing!

User-Comments: BIOS Boot-USB-Stick
biosflash 5.Jan.2017 07:00

You can use the Tool "RMPrepUSB" to reactivate (blue button) your usb pendrive.

Kledge 5.Jan.2017 06:41

Should've read a bit closer and realised that it said in red DO NOT WORK UNDER WINDOWS 10.

biosflash 19.Nov.2016 22:59

Try UNetbootin to create a bootable Live USB drive with FreeDOS, or use another USB pendrive.

wooxt3r 19.Nov.2016 19:25

Hey, i get a constant and annoying error with the software, i select everything i need for the software to create my usb but when i hit "format" i am prompted with the message "Failed to format the drive."

bass@nline 9.Nov.2016 23:54

Read your instructions to the letter. I got a desktop custom built with the MSI H55M-P33 mobo (AMI BIOS ver. 1.9) and wanted to update to the 1.10 ver. which adds support for 2.2 TB+ HDD and other new feature. For me it worked. All good. 5 stars. Great walkthrough.

Ifeanyi Ifemeje Kingsley 17.Oct.2016 23:48

I was updating my the bios 209 for Asus Zen book N501JW when I lost power and mysystem basically black screen and keyboard not working. Please if anyone could help me I would greatly appreciate it

Rafat Siddique 3.Oct.2016 02:15

Hey my laptop having the frozen Dell logo problem and someone suggested me to run this usb Bios program.I wanted to know will it work?please give me the download link.Thank you

biosflash 21.Feb.2016 07:03

I think, you can answer yourself this question.

Bones 20.Feb.2016 17:32

Good day sir. You say to choose the device from which to boot. BUT what if i dont have no video output at all, but PC is runing?

M.Collins 16.Feb.2016 03:35

When I tried Winphlash within windows, I got a checksum variable (104) error. Tried a Rufus bootable flashdrive with Winphlash16, but the BIOS ROM file failed to open.

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