How To Boot BIOS From USB (Windows 10)

How To Boot BIOS From USB (Windows 10)

USB drives can also be used to set up a thumb drive as a booting device for BIOS as well. For this, the thumb drive needs to be formatted in FAT format and must have the required boot sector file residing on the drive itself. This article will walk you through the process.

How to boot from a USB device?

  • To be able to boot from a device, you will need boot sectors. Boot sectors contain the information needed by the BIOS to enable it to boot using the device. You will have to create a bootable USB drive.
  • The next step is to copy files to the thumb drive. Now that the drive is bootable, you can put the essential files onto it. Copy all of the files that you put on the A: drive earlier on to your thumb drive. Be warned that if your floppy has a .BAT or CONFIG.SYS file and they use absolute path referencing to the A: drive, this could be a problem.
  • Once this is done, restart your PC, and go into the BIOS by pressing the [Del] button on your keyboard. ([F1], [F2], [Insert], and [F10] are all alternative keys that may be used here, depending on your model. Sometimes the PC will display a message telling you which key to press.)

N.B.: Some laptops allow you to set the boot devices using a Windows application. Toshiba, for example, does this with some of their laptops. The application is either a standalone application or an applet in the Control Panel.

  • Depending on the BIOS of your computer, you can set the USB stick as a boot device. If your PC's BIOS does not seem to support this, check if there is an update available. For some reason, most BIOS prefer to refer to the thumb drive than to a USB Removable Floppy Disk or to a USB Zip Disk.

If the settings mentioned do not seem to work with your PC, then do the following procedure.

  • Go into the BIOS, and go to the page that determines the boot order. (It is usually called Advanced Setup, Boot options, or Feature Setup.)
  • Try all USB drive variants. Start with USB ZIP, then USB FDD, USB HDD, etc.
  • To speed up the testing, disable all other boot devices. This goes for the 2nd, 3rd, etc, but also for Alternative boot devices.

How to access AMI BIOS and boot from USB?

AMI refers to AMIBIOS Simple Setup Utility.

  • To access it, go to Feature Setup and enable the USB Function Support, USB Function For DOS, and ThumbDrive for DOS options.
  • Go to Advanced Setup, and set the 1st Boot Device to USB RMD-FDD.
  • Reboot the PC. It should now boot from the thumb drive.
  • If this doesn't work, go to USB Mass Storage Device Configuration > Emulation Type and set it to Hard disk.
  • Go to the Boot Menu, and set the 1st boot device to USB-Stick.
  • Now you can exit the BIOS after saving the changes. If this does not seem to work, then you can try setting the Emulation Type value to Floppy or Forced FDD.

How to access Phoenix/Award BIOS?

  • To access the Phoenix/Award BIOS, go to Advanced BIOS Features<bold>.
  • Go to the <bold>1st Boot device, and set it to USB-ZIP.
  • Sometimes the device is listed as a USB hard drive under the hard drives menu. Finish by rebooting.

What is MKBT?

Introduction to MKBT

MKBT is used for installing boot sectors. It supports FAT, NTFS, and RAW boot sectors. It allows you to transfer a boot sector to floppy images. This allows you to create a bootable 2.88MB floppy image without needing a 2.88MB floppy drive.

MKBT is compiled as a Win32 executable and runs on Windows 95/98/ME (FAT) and Windows NT4/2000/XP (FAT and NTFS).

MKBT copies parts of the boot sector. The boot sector, the very first sector of a floppy disk, is 512 bytes long and looks like this:

  • FAT Boot sector
  • Offset Length Meaning
  • 0x0 3 bytes Jump instruction
  • 0x3 8 bytes OEM Name
  • 0xB 25 bytes BIOS parameter block
  • 0x24 26 bytes Extended BIOS parameter block
  • 0x3E 448 bytes Bootstrap code
  • 0x1FE 2 bytes End of sector marker

The BIOS parameter block and extended BIOS parameter block contains the information:

  • BIOS parameter block for FAT volumes
  • Offset Length Meaning
  • 0xB 2 bytes Bytes per sector
  • 0xD 1 byte Sectors per cluster
  • 0x0E 2 bytes Reserved sectors
  • 0x10 1 byte Number of FATs
  • 0x11 2 bytes Root entries
  • 0x13 2 bytes Small sectors
  • 0x15 1 byte Media type
  • 0x16 2 bytes Sectors per FAT
  • 0x18 2 bytes Sectors per track
  • 0x1A 2 bytes Number of heads
  • 0x1C 4 bytes Hidden sectors
  • 0x20 4 bytes Large sectors

Extended BIOS parameter block for FAT volumes:

  • Offset Length Meaning
  • 0x24 1 byte Physical disk number
  • 0x25 1 byte Dos: Current head
  • NT: Dirty flag
  • 0x26 1 byte Signature
  • 0x27 4 bytes Volume serial number
  • 0x2B 11 bytes Volume label
  • 0x36 8 bytes Filesystem ID

Command Line Syntax

The command line syntax is as follows:

Usage: mkbt [switches] <source> <target>

<source> The source file/drive which contains the boot sector to install <target> The target file/drive to install the boot sector on

Switches: -v Verbose mode -c Copy mode (no install) used for copying the boot sector(s) -x Expert mode (do not check drive A or B only) USE WITH CAUTION! -l=<xxx> Set Volume Label to <xxx>

Returns errorlevel 0 when OK, 1 when some error occurred.

Examples: To install boot sector from file "bootsect.bin" onto drive A: -> mkbt c:\os\dos622\bootsect.bin a:

To install boot sector from file "bootsect.bin" onto floppy image "288.img" -> mkbt c:\os\dos622\bootsect.bin c:\tmp\288.img

To copy boot sector from a bootable floppy in drive A: to a file called "bootsect.bin" -> mkbt -c a: c:\os\dos622\bootsect.bin

Installing a boot sector

To install a boot sector, MKBT follows the following steps.

First, it reads the source sector in buffer 1. Then, it reads the target sector in buffer 2. Then, it transfers the boot sector parts from buffer 1 to buffer 2. Finally, it writes buffer 2 to target sector.

Copying the Boot Sector

MKBT v1.3 (and higher) has a Copy boot sector option, which copies the complete boot sector. Previous versions only copied those sections that where needed to install it.

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