hard drive - noise and clicking
I mounted a 7200 RPM hard drive in my macbook pro and I often hear a click followed by the OS freezing for a while.
I've tried every fix I've found, like disabling the motion sensor, to keep maximum power on to the hard drive.
The new macbook pro has the same problem, but I'm not allowed to install the fix in the old one.
The hd is ok, the s.m.a.r.t. report is ok, apple mount 7200 on the new mac book pro unibody and a lot of them make this click noise before the patch(efi?), that unfortunately is just for the unibody.
I make a daily backup for the work and a weekly for everything else.
You symptoms are consistent with seek errors on the hard drive - the OS pauses waiting for the hard drive to thrash itself to pieces trying to move the drive heads to the next chunk of data.
You can run "verify disk" using Disk Utility - if it finds any errors, this may provide an additional indication of impending hard drive failure, and YOU SHOULD BACK UP THE DATA ON THIS DRIVE AS SOON AS POSSIBLE!
If you have an iPhone or iPod Touch, download DriveSaver's excellent free hard drive simulator app:
and compare the noises coming from your machine.
The 7200 RPM drives are known for having loud noises when installed in laptops. That is, as I understand it, the reason apple does not install them from the factory.
If the OS is pausing and you're hearing clicking, I would assume that there is a problem with the HD. Some HD's are just loud though. Best way to test it would be to mount another HD inside and clone (http://www.bombich.com/index.html) your system to see if the sounds and pausing OS problem continues.
First, reassure yourself the drive is OK. The SMART verification in Disk Utility, TechTool Pro, SMART Reporter, and others is not very good--the warning thresholds are set so high the disk is usually toast by the time you have a clue. My favorite app for this is SMART Utility, available on versiontracker.
BACK UP EVERYTHING NOW! Im no technical expert but one thing I do know is that clicking and pausing is a VERY bad thing.
I had the same problem about two months ago and it was an indication to a subsequent HARD DISK MECHANICAL FAILURE. I lost a fair amount but luckily nothing to point toward a disaster. The drive had to be taken out and I took the opportunity to upgrade the drive to a seagate 500GB 7200rpm, and i'm now running a happier machine.
I'm not sure if "keep maximum power on to the hd" is the power mode it operates in or if incorporates other settings such as spin down time. Make sure the drive isn't just going to sleep by upping the sleep timer. This would cause both a click and a noticeable pause to your OS.
David is correct though, first thing to do with any questionable drive is to pull your data from it.