Old Compaq corporate PCs can be picked up very cheaply (I got a Pentium III/1 GHz/512 MB RAM machine for a project for £59 the other day). They are well-constructed, slim, and it’s easy to access the innards. Unfortunately, their utility as headless devices is hobbled by one frustrating annoyance: they won’t boot without a PS/2 keyboard attached.

Fortunately, there’s a solution to this, but it’s very well hidden and rather counter-intuitive: in fact, you need to set up a boot password to do it!

I found the instructions in the middle of a discussion thread on touchscreen kiosks, and I’m going to replicate them here so that I can find them again:

  1. Set a power on password (under security in the BIOS settings)
  2. Go back into security menu and select the new item that appears just below power on password, it’s called password settings or suchlike.
  3. Enable Network server mode

Your machine will now boot happily without a keyboard, and in case you wonder also without asking for the password you just set.

The keyboard, if anyone does plug one in, is disabled except during power up when you can still press F10 for setup. Doing so will then lead to a prompt for the password.

It worked for me, though I did take more action:

  • Write the password on a sticky label and affix it to the machine.