h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

My PB is getting a bit noisy, something is running constantly that didn't used to (or used to be really quiet). I can't tell if it's the fan or the HDD. Is there any way to know? Can I spin the HDD down manually in OSX?

I had a whole bunch of safari windows open, including a couple with youtube vids loaded. CPU was at something like 70% I think. Once I quit all those and reopened Safari, and quit a bunch of other programmes the noise is quieter but still constant.

Any ideas?

thanks,
kea.

You can use something like iStat to see if the fans are spinning and what the internal temperature is, etc.

But you should also be able to tell from the location of the sound. Fans would sound more like they are coming from the back or side - where the vents are - while the hard drive would sound like it was coming from under the keyboard or someplace like that. I'm not sure where the hard drive is exactly, but that's the basic idea.

Anyway, my guess is the fans. When hard drives start to get noisy at the end of their lives, you tend to hear a rattling or clicking, possibly a screech. Fans just whir, and the mac is known to spin up its fans from time to time and some software like Firefox and Flash is known to affect it - resetting the power manager may help, but I don't recommend it unless you have other problems like the battery not charging properly. Often, just restarting the mac will set the fans right.
http://support.apple.com/kb/HT1411

Thanks d'El. A restart did make a difference. I've tried istat, and the temps seem ok. But this morning it's saying the fans aren't spinning yet I can still hear the sounds, so I guess that means I'm listening to the HDD. And perhaps when it's really noisy I'm hearing the HDD *and* the fans. The powerbook does run pretty hot sometimes.

I've never been able to figure out where the HDD and fans are, except there are two fans I think, left and right.

The thing that is worrying me is that the computer used to have quiet times, even when I was working, and that doesn't seem to be happening now, it seems the noise is there all the time. Would the HDD stop spinning down with age or wear?

I am having trouble with the battery, but I assume it's at the end of its life. Istat says its health is 29%

If it's an expensive HDD, it will likely have a large amount of cache built-in. Thus, when it was new and there wasn't much on the HDD it's possible that you were getting everything you were using into the cache and the drive was spinning down. But it's unlikely that this is the phenomenon you are noticing.

There's an option in the energy saver system preference that determines whether the hard drive spins down or not. Maybe that got toggled accidentally?

But it could just be that the software you are using now accesses the hard drive more often. This could be true even if you're using a new version of the same old program.