Thom, thanks for the advice; it does have a firewire port and I already have an external hard drive attached via USB and firewire. I do run OS X when I need but basically find I'm happy with OS 9 for the most part. Does it need a repair shop to replace the HD? regards michaelP > Michael, > > It sure is something to be concerned about. You need to make a backup > and replace the hard drive if you have not already done so. I don't > remember, does your machine have a firewire port. Most likely not. If > not, get an external USB drive and copy over all your data files, then > replace the HD. > > If you can afford it, I would get a newer Mac, even a used one; > preferably something running OSX. That would be the most cost effective > thing to do. > > Thom > > > michaelP wrote: > >> hi folks >> >> using: >> >> *iMac G4 800Hz, OS 9.2.2, 384 Mb RAM, 40 Gb H/D (and a few years old) >> * >> prob: >> >> recently, a few minutes after booting up I hear a humming whirring >> sound that starts fairly softly but builds up over the next half hour >> to quite an irritating and distracting racket; I presume this is the >> hard drive or a fan? Another otherwise identical friend's iMac is as >> quiet as a (silent) mouse. Is this something I should be concerned >> about? And, if so, what can I do to repair or ameliorate it? Any thoughts? >> >> thanks in anticipation >> >> michaelP