deutsch BIOS Boot-Diskette - Howto: BIOS-Update per bootable Diskette

D i s k e t t e


A guidance how to create a Boot-Diskette (MS-DOS v6.22) to perform a BIOS update.

see also: BIOS-Update Howto: step-by-step instruction
see also: BIOS Update per bootable USB-Stick
see also: BIOS Update per bootable CD


Important: this method creates a Boot-Diskette for DOS. Due to the size limitation of a 1.44MB floppy disk, you can only use a BIOS file and flashtool whose total file size is max ~1.2MB!

Recommendation: i prefer to use the method BIOS Update per bootable USB-Stick!
A bootable pendrive has no size restrictions and more importantly: you can create a BACKUP before updating the BIOS - and that's always a good idea!


The following tools are needed:

  • rawrite - free Floppy image tool, Download from manufacturer's website
  • Ultimate BIOS-Boot-Edition:
    - floppy.img (the boot image contains only the most important MS-DOS operating system files)
    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 DOS-Boot-Diskette

  • Open the Ultimate BIOS-Boot-Edition and the folder boot_floppy_disk
  • Copy the boot image file floppy.img to your hard disk.
  • Start rawrite and choose the menu Write (1.).
  • Insert the path (2.) to the boot image file floppy.img.
  • Click the Write-Button (3.) to create the bootable DOS-Diskette.
  • Close rawrite.
  • 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 diskette.
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 Diskette

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

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

  • Now you can start the BIOS update. Remember: you can only backup your old BIOS onto the Diskette if sufficient space is available! But if your harddisk has a FAT16- or FAT32 partition, it would be a good idea to copy your 2 BIOS files to this partition, and to start the update/backup from your harddisk.

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

Happy flashing!

User-Comments: BIOS Boot-Diskette

Einträge: 3

kishan 9.Aug.2023 14:19


Rajbeer 20.Mar.2023 08:50

Bios tool all software kit

luiz 11.Jul.2011 21:20

muito bom!