[UnixMac]

I just noticed that one of my HD's is showing as "disconnected" in temp monitor (no temp data), however, it functions just find, and all the cables are connected on it as far as I can tell... any one have similar experiences? it's on my WD Raptor..

[jamil5454]

That's kind of weird. The HD's temp sensor is inside the hard disk where the platters are. Has it ever worked before or did it just now start acting up? Your Raptor may not be supported.

[UnixMac]

Originally posted by jamil5454:
That's kind of weird. The HD's temp sensor is inside the hard disk where the platters are. Has it ever worked before or did it just now start acting up? Your Raptor may not be supported.

no my knowledge it has never worked. But the software author said my particular raptor is supported, so I have no idea. I can call WD next I guess, but I got my drive from a Gray Market channel so they may not support it!

[tooki]

Are you sure you're not confusing the HD's internal temp monitoring (which I don't believe any HD communicates with the computer) with the G5's temperature sensor for the HD cooling zone?

tooki

[UnixMac]

Originally posted by tooki:
Are you sure you're not confusing the HD's internal temp monitoring (which I don't believe any HD communicates with the computer) with the G5's temperature sensor for the HD cooling zone?

tooki

I may well be, however the connections to both my HD' are identical yet only my Maxtor is sending a temp reading to Temp Monitor...

Anyway, the oddest thing happened this morning... it works!

I didn't do a single thing to the physical connection, nor Temp Monitor, but all of a sudden the sensor (where ever it may be) is sending back data.

Oddly, the upper (Raptor) is reading 32C while the lower Maxtor is reading 43C.. I wonder if that's air-cooling related, and no so much drive related?

btw.. on a side note... it was interesting to watch the drives slowly warm up from about 15C to their current temps over the past 3-4 minutes..

[P]

The HDs internal temp sensor can be read back by the OS. It's part of SMART, and this is the way that temperature monitor programs get it. The temperature that your program shows for the HD temp is indeed the inetrnal sensor. I can't explain what happened to your drive though...

[tooki]

Ah! I didn't know SMART was that detailed.

tooki

[UnixMac]

Originally posted by P:
The HDs internal temp sensor can be read back by the OS. It's part of SMART, and this is the way that temperature monitor programs get it. The temperature that your program shows for the HD temp is indeed the inetrnal sensor. I can't explain what happened to your drive though...

I wonder if it's not a bug with the latest Temp Monitor, cause I noticed my GPU sensor also dropped off line for a short while, but when I re-launched Temp Mon it came back.

It could also be some very odd things happening in my OS X (Hope not!)

[bighead]

Originally posted by tooki:
Ah! I didn't know SMART was that detailed.

tooki

I don't know if SMART requires a temperature sensor. My PowerBook's new 100 GB Seagate doesn't seem to be recognized by Hardware Monitor for temperature reads, even though Disk Utility sees it and says SMART verfied.

It could be that the temperature sensors are apart from SMART, and the guy who writes HW/Temp monitor hasn't reverse engineered every temperature sensor out there.

Anyone know nitty gritty stuff about SMART and HD temperature sensors?

[UnixMac]

Originally posted by bighead:
I don't know if SMART requires a temperature sensor. My PowerBook's new 100 GB Seagate doesn't seem to be recognized by Hardware Monitor for temperature reads, even though Disk Utility sees it and says SMART verfied.

It could be that the temperature sensors are apart from SMART, and the guy who writes HW/Temp monitor hasn't reverse engineered every temperature sensor out there.

Anyone know nitty gritty stuff about SMART and HD temperature sensors?

Having spoken now to the guy who wrote temp monitor, I would have to believe that he is a most capable programmer and that the problem lies in that all drives are different, and that he has to constantly modify the software for them. But it can also be an OS thing as the temps are all monitored by OS X ultimately and not on some kind of hardwired connection to Temp Monitor.

[P]

It depends on the exact version of ATA and SMART if the temp sensor is required or just vendor optional. It is not included in ATA-5, the oldest version I could find a spec for, but Maxtor has added it anyway on some drives. However this page

http://smartlinux.sourceforge.net/smart/

says

Thermal monitoring is a more recently introduced aspect of SMART, designed to alert the host to potential damage from the drive operating at too high a temperature. In a hard drive, both electronic and mechanical components - such as actuator bearings, spindle motor and voice coil motor - can be affected by excessive temperatures. Possible causes include a clogged cooling fan, a failed room air conditioner or a cooling system that is simply overextended by too many drives or other components. Many SMART implementations use a thermal sensor to detect the environmental conditions that affect drive reliability - including ambient temperature, rate of cooling airflow, voltage and vibration - and issue a user warning when the temperature exceeds a pre-defined threshold - typically in the range 60-65°C).

So it seems that temperature monitoring was only recently made part of the standard.

[OreoCookie]

1 Unscrew everything.
2 Open the harddrive's enclosure.
3 Reconnect

No, seriously, hds have internal sensors (or not) that monitor the temperature of the drive. Of three harddrives I tested with smartmontools (command line tools for monitoring hds, works fine on MacOS X) had working temperature sensors.