Hood,
    Seems more like a software thing to me.  I've had problems all along with the machine booting up in a funky state, and re-booting always makes it happier.  It's not like it's flaky.  Once it's up and running well, it'll run well forever.  It just sometimes boots up in a wierd state.  Mach is the only app. I've had a problem with.  The machine is a dinosaur - circa '99 or so, and will be replaced shortly.

Regards,
Ray L.