Hard Drive Sporadic Rhythmic Activity?
I have four external hard-drives (1 usb 3 firewire -smallest being 160GB all new within a year or so.) all of which make a sporadic sound I am wanting to understand. When I posted this almost a year a go, I was told the drive was failing and to replace it. Not only has nothing failed, but I now know that this happens with a Western Digital, Fantom, LaCie, Maxtor USB or Firewire drives and all from new. And no matter how much data is stored. But I assume some data has to be stored. I erased one drive with zeros and ones considering it might clean the drive and did not notice the activity through a day, but on a next day placement of 60GB of mp3s heard this activity again. I am thus considering that this activity is a maintenance or indexing or similar function of the operating system, but I do not know.
(Surprising to me was also that before placing the mp3s I run Datarescue & found that much of the data was still recoverable even after erasing with zeros & ones. Thus I conclude permanent elimination only occurs by writing to every sector of the drive. A late discovery given a past sale of a powerbook only 0ed & 1s)
Simply stated, the sound is an activity of the hard drive (I assume the head, but...) in the absence of my calling it to do anything. It has a specific repetitive sound rhythm as though some maintenance call is asking the head to do a pattern which produces a same repetitive clicking movement and rhythm. It lasts perhaps a minute or so and then stops.
I can stop the pattern at any time simply by making a call to the drive. Such as from the finder, in list view, click on a folder not recently opened. If I click on a same folder as already clicked on, it does not stop it. I assume that is because the operating system is reading from cache and not calling to the hard drive. (on a restart or boot up, any finder opening to the hard drive will stop the rhythmic sound.)
It annoys me because it is a sound I do not understand, I did not call for, and it sounds like an activity that would wear the drive out sooner than necessary.
So what is this or if not known, what are the possibilities or what further tests and observations might I do to narrow the list of possibilities?
&
Is the frequency of this activity manageable?
Thanks
harmz
Powerbook 12 1.5GHz G4, Mac OS X (10.4.7), MATSHITADVD-R UJ-835E