Does Power-Management Affect a Hard-Drive’s SMART Statistics

Among the various fields in a hard-drive’s SMART statistics, a few are flagged as “life-critical”, that is, those values determine the primary health of the drive and how long it may have left before catastrophic failure. Regardless, each field contributes to the overall health of the drive.

I have always wondered about how power-management affects SMART data (and before the electric company recently jacked prices, I was resistant to use power-management for fear of adding wear to the drives, specifically because the SMART data keeps logs like this, thus allowing me to visibly see the wear accumulating). Basically, does power-management affect a hard-drive in the same way as turning the whole system on or off?

There are at least two fields in particular that would ostensibly be directly affected by power-management:

• Start/Stop Count

• Drive Power Cycle Count

• Load Cycle Count (which usually equals Drive Power Cycle Count)

while some other fields would probably be indirectly affected:

• Spin Up Time
• Spin Retry Count
• Power Off Retract Count
• Calibration Retry Count

and some fields would be directly affected, but positively:

• Power On Hours Count
• Temperature

Anyway, I’ve tried testing it, but have not been able to determine or confirm if power-management functions affect the SMART data. That is, if an idling system shuts down a hard-drive that is not being used, or the whole system goes into standby mode, would the hard-drive log it in the SMART table (eg incrementing the Start/Stop and Power Cycle counts)? In other words, from the drive’s point of view, is power-management the same as normal shutdown/startup?