** Bob Dove b.dove@virgin.net [2006-06-06 12:54]:
Silly quezzie time - what is the best orientation for a hard drive? My son in law has just had his office and network moved, and the IT specialist (their term/claim) re-installed with all the towers horizontal rather than vertical. Now I know that there are some vertical external HD cases but thought they might have contained 'special' HDs. Presume some gyro force generated so no silly angles - but otherwise? Any wise old owls out there with the definitive???
** end quote [Bob Dove]
I doubt there is a definitive answer as you would probably have to look at the fragility specs for each make/model of drive and combine that information with further testing on the case to work out how the chassis passed shock and vibration through to the drive :) There was a time when PC systems from the likes of IBM were tested for internal air flow, temperature, vibration, etc. to ensure the machine would last - a far cry from throwing parts from any manufacturer together and swapping in new cards, drives, etc.!
In simple practical terms there is likely very little difference for a modern drive sitting in a standard case on a desk. These things have probably changed somewhat since I worked on fragility and package testing for IBM in the early/mid nineties (circa 80 to 540M 'low cost' IDE and 4G SCSI units, etc.).
The wear on the bearing would be best with the drive mounted with the circuit board downwards since the weight distribution would be even. Any sudden shocks would, however, if out of spec, cause the head to hit the platter and cause damage (serious stuff if you spread particles all over the place in there!), whereas you would be more prone to soft errors (retries that slow the drive down) if the head is merely being knocked off track as when used in a vertical orientation.
Of course technology has moved on leaps and bounds since my time, and tolerances have become tighter by orders of magnitude - not to mention my memory showing signs of rust ;)