I recently bought a Dual 1.25 Powermac (OS 9 & X bootable). i know a lot of people complain about the noise of the fans, but i also hear another noise usually every 1/2 hour or so. it sounds similar to a cassette tape rewinding. it only lasts a second or 2 but its annoying. I think it might be the hard drive, but i am not positive. if anyone has any thoughts or information about what this could be, please let me know. thanks.