WilliamG

In the case of the Backup Plus/Expansion, we know what drive it is. There just seems to be some disagreement about whether it's a PMR or SMR drive there. Actually, you don't know. As seen previously, there may not be one drive used for all of the Backup Plus/Expansion. Seagate has been know to ship multiple drives under the same labeling, including this case Seagate could easily have shipped PMR and SMR drives under the Backup Plus/Expansion label. Could have. But as far as I'm aware ALL 5TB Backup Plus and Expansion are ST5000DM000. Whether that is a PMR or SMR drive I don't know.

In the case of the Backup Plus/Expansion, we know what drive it is. There just seems to be some disagreement about whether it's a PMR or SMR drive there.

Reading this thread, it would have been useful if people had mentioned the model of the drive they were discussing because some people were talking about a conventional drive while some were discussing an SMR drive. There are several 5 TB Seagate drives available at the moment, each designed for a particular application. The only one that uses SMR technology has "AS" in its model number, such as ST5000AS001. They work very well in external USB cases and it isn't Seagate's fault if people break open the cases and use the drives as they were never intended to be used. The ST5000DM000, in contrast, is a conventional non-shingled drive. If the ST5000DM000 is not SMR, I wonder why people are having odd performance issues with them which seem to be related to the SMR tech? Unless the performance issues are nothing to do with SMR in the first place, because these drives are PMR? To confuse things further, here is "legit" reviews with their review of the ST5000DM0000, stating it's SMR. Ahhh, gotta love the total confusion. I have no idea either way what type of drive it is. http://www.legitreviews.com/seagate-barracuda-st5000dm000-5tb-desktop-hard-drive-review_161241

Quoting myself to update this thread. Still running a bunch of these (12 now) 5TB Seagates connected to my Mac mini over Thunderbolt, running SoftRAID 5. No issues running RAID 5. Performance definitely decreases when the files are tiny and there's zillions of them (to be expected), but still getting excellent large-file throughput speeds despite several of the RAID 5s being quite full (277GB free on one of the 4x 5TB RAID 5s - 15TB available originally). These are ST5000DM000 drives. I'm right now running a verification that all data can be read, and that there's no bad sectors on 8 of them... Here's a picture of the in-progress verification.. (sorry for the crap resolution but was limited to 192KB).

Just received 4x 5TB Seagate Expansion disks to put into my second Thunderbolt 4-disk array. These disks (ST5000DM000) came with CC44 firmware. No idea what the changes are from CC41, but they're working just fine, much like my CC41 disks are. Approximately 500MB/s read/write in OS X in RAID 5 configuration. That said, the head-parking makes a TERRIBLE noise and is far too often, but again - easily fixed in OS X with the HDAPM launch daemon.

Feel free to check me out on Macrumors forums (same username). You can see my posts on what enclosure to buy, my experiences with the Seagates, and my long-standing contributions to the community there etc. FYI, I'm about to buy a second enclosure and another 4x 5 Seagate disks. I must REALLY work for Seagate, though.

I registered here just to reply and say this thread is full of nonsense. Telling everyone to avoid a Seagate disk because of a few people's issues is just ridiculous. For reference, I have 9 (nine) of these 5TB Disks, bought in the USA in Seagate Backup Plus units. I had 4 of these running externally for a while (4-5 months) - connected to a Mac mini 2012 running SoftRAID 4 - two sets of RAID 1 over USB 3.0. No issues. (since upgraded to Thunderbolt enclosure) I have 2 running now for about a month, connected to an Asus Sabertooth Z87 motherboard. No issues - 180MB/s read/write or thereabouts. I have 2 running a simple RAID 1 over Thunderbolt connected to my Mac mini 2012. I also now my original 4 of them in an OCZ Thunderbay 4 enclosure - running RAID 5 over Thunderbolt connected to my Mac mini 2012. And then I have a spare 5TB just in case I have a failure. Again, NO issues with any of these drives. The only thing I had to was run the Mac HDAPM tool to prevent the head-parking issue that OS X is infamous for, but I had no performance issues prior to running the tool, and only did so because I didn't like the noise the head-parking sound made when running media in a quiet movie room. I did the same thing with my older 2TB Western Digital drives, too, so this is not unique to the Seagates. So again, to the OP, your experience is certainly not everyone's, and telling EVERYONE to avoid Seagate 5TB Externals is just madness. PS I have several friends with ~15 5TB Seagate drives between them, and neither of them has any issues, either.