@RhianB.
Nice find, I'm sure you'll enjoy it, and at 1GHz not too much of a 'chestnut' warmer. And with a fuctional battery too, which is often unusual for these older PBooks.
I've just finished a complete tear-down, and refurb of my second 12", a PowerBook6,4 model. I initially had some doubts if the fan was operating correctly, and knew for sure from the poor sound that the internal speaker was damaged.
I completely refurbished and re- lubed the fan, but didn't think to function-test it prior to re-installation, wish I had!
I also repaired the damaged speaker cone with a light neoprene glue.
On completion it booted up ok, sound is no longer distorted, but there's not much volume from the internal speakers (though perfect with headphones).
Alas, it auto-powered off after 5mins.

Rebooted ok, but powered off again after a few more mins. Pulling the keyboard, my fears have been confirmed, the fan is not turning. So in all, it was somewhat of an abortive refurb attempt.
So if anyone has or knows of a doner 12" alu PBook (it's a 1.33GHz), I'm in Prince Charles mode. All ears.
