Dell laptop BIOS update using FreeDOS and ISO Master

I recently needed to update the BIOS on a Dell Inspiron 630m laptop. The file, available from Dell support, is a DOS executable named MX51_A04.EXE.

I had two problems with this file: (1) Windows would not boot, so I couldn’t run the file using Windows. (2) The laptop had no floppy drive, so I couldn’t easily boot into DOS.

Now, one can solve this problem by booting from a FreeDOS LiveCD to run the file. But then you have to figure out how to get and run the MX51_A04.EXE file from within the FreeDOS environment. Various websites suggested methods using USB flash drives, but I couldn’t get this to work.

Instead, I was able to add the file to the LiveCD ISO image before I burnt the CD. Here’s how it worked:

  1. Download the FreeDOS LiveCD called fdfullcd.iso (153MB).
  2. Under Linux or Windows, install and run ISO Master.
  3. Load the fdfullcd.iso in ISO Master and then add the MX51_A04.EXE file to it.
  4. Save the modified ISO under a new name.
  5. Burn the modified ISO to a CD and boot from that.
  6. When you boot the laptop using this modified FreeDOS LiveCD, be sure to choose the LiveCD mode and not the install option.
  7. Once you have a DOS prompt, the command X: will switch you to the X: drive, where you’ll find the contents of the CD and the BIOS update file.
  8. Run it, cross your fingers, and reboot.