I was given my sparcstation 5 by Durham University by way of the Durham University Computer Society (thanks!). Unfortunately, the boot PROM was passworded, making it impossible to interfere with the boot process, e.g. to boot from a CD-ROM rather than hard disk.

I googled around and most advice suggested you needed to buy a new boot PROM chip. I didn't fancy that much. I found a single usenet post describing a method of clearing the boot PROM but no supporting posts saying it worked.

The technique


the yellow-stickered one


The PROM removed

  • boot the machine and enter the boot PROM. Get a password prompt.
  • Crack open the case and remove the PROM chip whilst the machine is on.
  • Hit enter on the password prompt: since it can't confirm the password against the PROM, it lets you through.
  • Re-sit the PROM chip in the machine, whilst turned on.
  • You now need to clear or disable the PROM password. Either:
    • setenv security-mode none to disable the password, or
    • password to be prompted for a new one.


This technique worked fine for me. Thanks to Karl Goetz for confirming it worked for him too.

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