Hi I have a G4 (Sawtooth) 400, I bought it in Jully of 2000, just before they released the new Gigabit models, so I believe it has an ATA 66 IDE controller. Anyway I have two hard disks, one for classic and another for OS X. The one for OS X seems really unresponsive at certain times, and at these times the machine's internal speaker actually sends me a beep code(?) which I think means that the Hard Disk's buffer is overloaded. If this is the case, do you think it is a flaw in the Hard Disk, or could it be something else? This is not the original hard disk by the way. And if this is not the case what is the beeping mean?