Hitachi 5K3000 drives click when idle (sometimes)

[dolphin842]

Hi all,

When I turn on either of my Hitachi 5K3000 (2TB) drives (currently hooked up via external enclosures), they often (though not always) make a consistent clicking sound when idle. I originally thought something in OS X was making them thrash (the clicking does sound similar to normal data access), but the sound is present if I only turn on the hard drive (leaving the Mac mini off). The drives mount and function normally from what I can tell, and if OS X needs to access something from the drives, the clicking stops for the duration of the I/O activity, then resumes. After turning on the drive, the clicking can last anywhere from several minutes to an hour or so (and there's roughly a 5-10% chance it wont make any clicking sound at all when powered on).

Here's an aac file of the noise (it gets louder for a few seconds toward the end only because I put my iPhone directly on the enclosure).

Because the sound eventually goes away after a while each time I boot up, I've let this linger for several months without doing much of anything about it. Regular Disk Utility scans don't show any problems, but I'm really starting to wonder if I should try to RMA these just to be safe.

Anyone have any thoughts?

 

[Mattie Num Nums]

Clicking at idle is normal. I wouldn't worry about it to much unless its more of a clicking/stuttering sound following but a rewinding or grinding sound. Thats the sound of bad news.

 

[dolphin842]

Yeah, all it does is click like in the audio file. They've been working fine for months, even while clicking, so I guess if it were a sign of problems, something would have happened by now. Any idea of what the drives are doing when they click like that?

 

[chown33]

Any idea of what the drives are doing when they click like that?

Maybe thermal recalibration. Google it.

 

[dolphin842]

Maybe thermal recalibration. Google it.

Ah, looks like that might be the answer, thanks!

From http://stason.org/TULARC/pc/pc_hardware_faq/3_14_What_is_Thermal_Recalibration.html

3.14 What is Thermal Recalibration?

When the temperature of the hard drive changes, the media expands slightly. In modern drives, the data is so densely packed that this expansion can actually become significant, and if it is not taken into account, data written when the drive is cold may not be able to be read when the drive is warm. To compensate for this, many drives now perform "Thermal Recalibration" every degree C (or so) as the drive warms up and then some longer periodic interval once the drive has reached normal operating temperature. When thermal recalibration takes place, the heads are moved and the drive may sound like you are accessing it. This is perfectly normal.

There are other reports out there of this occurring regularly with Hitachi drives, so I think I'm in the clear for now.

 

[Makosuke]

It's funny, I'd just noticed my server drives making this noise a few days ago, and was wondering both what it was and whether it was the 5K3000 or WD GP. Looks like it's the Hitachi, and I've been saved Googling it myself.

Unrelated aside: Who's that in your avatar, dolphin842?

 

[dolphin842]

Unrelated aside: Who's that in your avatar, dolphin842?

No idea actually . Just found it on the internet. Here's the full size version. More enterprising otaku than I may know whether she's from a series or an original character.