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I use a 640 GB StoreJet Transcend (0x2329) with ZEVO Community Edition 1.1.1 on OS X 10.8.2.


Is this drive Advanced Format?


I submitted a request for technical support to Transcend but the first response was gibberish so I don't expect a reasonable follow-up.

Models at are similar but different sizes (not 640 GB). Mine is probably 25M2 (TS640GSJ25M2):

screenshot from a Transcend support area

Unless I'm missing something, nothing currently in the Transcend support area tells me whether the drive is Advanced Format.

From System Information in OS X 10.8.2:

StoreJet Transcend:

  Capacity: 640.14 GB (640,135,028,736 bytes)
  Removable Media:  Yes
  Detachable Drive: Yes
  BSD Name: disk3
  Product ID:   0x2329
  Vendor ID:    0x152d  (JMicron Technology Corp.)
  Version:   0.00
  Serial Number:    322549FBA004
  Speed:    Up to 480 Mb/sec
  Manufacturer: JMicron

History for the ZFS pool shows creation in March 2012 – 

macbookpro08-centrim:~ gjp22$ zpool history zhandy | grep create
2012-03-14.17:29:37 zpool create -f -O compression=off -O copies=1 -O casesensitivity=insensitive -O snapdir=visible zhandy /dev/dsk/GPTE_1928482A-7FE4-482D-B692-3EC6B03159BA
2012-06-22.15:51:16 zfs create zhandy/Pocket Time Machine

At that time I almost certainly used ZEVO Setup Assistant to create the pool.

macbookpro08-centrim:~ gjp22$ zpool get ashift zhandy NAME    PROPERTY
VALUE   SOURCE zhandy  ashift    0       default

If I discover that the drive is Advanced Format, a different ashift value will be appropriate.

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I added a bounty for attention … in retrospect, it might be better to think of this question as requiring authoritative reference. That reference is not found in the Transcend area – or am I missing something? – Graham Perrin Dec 5 '12 at 5:02

In linux you can run hdparm -I /dev/sda to see physical sector size, so if you can boot live linux CD/DVD/USB, then you can get your info. (e.g. SystemRecsueCD)

Didn't find a Mac port of hdparm, but I saw references on internet saying that diskutil on Mac is a complex utility that can handle things like hdparm. I never used Mac OS so this is just a blind idea.

Manual on diskutil

Not a complete answer I guess, but it's more space in here, hope it helps :)

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This answer is more for the linked question (about methods) than for this question about a specific drive. There's emulation – as some people put it, a drive may lie (not tell the truth) – we don't know whether this drive emulates something other than its true sector size. And so the results of things such as hdparm may not reveal the truth. – Graham Perrin Dec 5 '12 at 4:58

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