Hard drives continue to remain the storage media of choice for cost-conscious consumers with bulk storage requirements. HDD vendors have typically used their 2.5" drives for bus-powered high-capacity models. This market segment has been stuck at the 4TB mainstream capacity point for a few years now, with the z-height of the models coming in at well over 15mm. Earlier this year, Seagate announced an update to their massive 5TB Backup Plus Portable, while also introducing a new svelte 2TB Backup Plus Slim external hard drive. Both of them adopt SMR platters (similar to the Backup Plus models being sold since late 2016), and given the performance impact of SMR, today we'll be taking a detailed look at how SMR in bus-powered hard drives behaves for consumer workloads.

Introduction and Product Impressions

The number of vendors delivering portable, bus-powered hard drives is limited: only Seagate, Western Digital, and Toshiba serve this market. Of these, only Seagate has a 5TB model in the market currently. While Western Digital and Toshiba use conventional magnetic recording (CMR) for their 2.5" hard drives, Seagate makes use of shingled magnetic recording (SMR). This enables higher data storage density in their platters, which, in turn enables them to deliver the highest capacity 2.5" hard drives. The high density platters also allows them to deliver slim hard drives (at industry-leading capacity points taking thickness into consideration). Today, we are taking a look at the high-capacity Seagate Backup Plus Portable 5TB drive and the ultra-thin Seagate Backup Plus Slim 2TB dual-platter drive.

Mass-market bus-powered hard drives typically employ a USB 3.0 micro-B interface port (contrast this with the LaCie Porsche Design Mobile Drive that comes with a Type-C port). The Seagate Backup Plus models we are looking at today belong to that category. Seagate's portable drives have come with different value additions over the last several years. A few years back, the drives came with free cloud storage (OneDrive) for a limited time. Recently, we have seen them bundle a two-month subscription to Adobe's Creative Cloud package with select models. The Seagate Backup Plus models also come with value additions: In addition to the aforementioned Creative Cloud, Seagate also offers the Mylio Create cloud-based photo organization feature.

Package-wise, the two drives are remarkably similar. They come with a 18 inch. USB 3.0 Type-A male to Micro-B male cable. The cable color depends on the color of the drive itself. Other than that, we have a quick-start guide and a bunch of papers describing the value additions.

The drives come pre-formatted in exFAT, guaranteeing compatibility with both Macs and Windows-based systems. A setup executable is also available to help users get step-by-step guidance for product registration, warranty activation, and redemption of the value additions.

Moving on to the technical details, we get a quick understanding of the internals using CrystalDiskInfo.

Internal Drive Characteristics

Typical of bus-powered hard drives, both the Seagate Backup Plus Portable and Slim are 5400 RPM drives. It turns out that the internal drive of the Portable (the ST5000LM000) is available in the retail market as a Seagate BarraCuda Compute drive, while the one in the Slim (the ST2000LM007) is marketed as a Seagate Mobile HDD.

We have reviewed a number of bus-powered hard drives over the last few years. The table below presents the detailed specifications and miscellaneous aspects of all those units and how the two Seagate Backup Plus models being reviewed today compare against them.

Comparative HDD-Based Direct-Attached Storage Device Configurations
Bridge Configuration SATA III to USB 3.0 Micro-B SATA III to USB 3.0 Micro-B
Power Bus-Powered Bus-Powered
Internal Drive ST5000LM000-2AN170
5TB 5400 RPM 2.5" SATA Hard Drive
Seagate Barracuda Compute
2TB 5400 RPM 2.5" SATA Hard Drive
Seagate Mobile HDD
Physical Dimensions 115.3 mm x 20.9 mm x 80 mm 114.8 mm x 11.7 mm x 78 mm
Weight 265 grams 126 grams
Cable USB 3.0 Micro-B to Type-A USB 3.0 Micro-B to Type-A
Evaluated Capacity 5TB 2TB
Price $95 $70
Review Link Seagate Backup Plus Portable 5TB Review Seagate Backup Plus Slim 2TB Review

The key things to note here include the thickness of the Backup Plus Slim and with its weight. With a z-height of 11.7mm, it is comfortably the thinnest external hard-drive we have reviewed. At 126g, it comes in at barely half the weight of the other models in the above table.

In the rest of this review, we first take a look at our standard direct-attached storage benchmarks. Following this, we have some performance measurements from a typical external HDD real-world use-case. Finally, we talk about power consumption and provide some concluding remarks.

Direct-Attached Storage Benchmarks
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  • Sivar - Tuesday, June 18, 2019 - link

    This is an interesting way to look at it, but it makes sense.
    Benchmarks for small writes have not gone well for early SMR drives, though that may have improved since. I suspect they would make great storage drives for movies, music, images, or other large files.
  • abufrejoval - Wednesday, June 19, 2019 - link

    I wonder about the command set, too. Crystal disk info typically mentions TRIM support and doesn't show it the posted picture. Dunno if it asks HDDs for TRIM or if the command set is different.

    There must be some way to control that behavior otherwise the hyperscalers wouldn't have co-invented them with the HDD manufacturers.
  • Arbie - Tuesday, June 18, 2019 - link

    Thanks for the excellent article evaluating these drives and describing the state of SMR. It's good to see that the process has improved.

    Seagate nowadays makes it very difficult to determine before purchase if a drive is SMR or CMR. As a result I've gotten into the habit of just going for other brands first - not the best approach, certainly, but I'm only willing to do just so much research.
  • oRAirwolf - Tuesday, June 18, 2019 - link

    I use 7 of the 4TB Seagate drives shucked out of their enclosures in a Dell R620 SFF sitting in a data center. The drives have cold air constantly moving over them and see use as a RAID 5 storage array with the Dell H710P (LSI SAS2208) RAID controller handling everything. They are used for media storage and see very little write activity. These drives drop like flies. If I get 6 months out of them, I feel lucky. Of the 7 drives in the server over the past 1.5 years, I have had to replace 5 of them. I only use them because of their density and the fact I am kind of locked into them at this point. I would not recommend these things to my worst enemy, though.

    I would definitely spend the extra on a WD if it is going to be used with it's external enclosure. Sadly, the WD drives have the USB connector directly soldered to the drive, rather than using a SATA to USB adapter like the Seagate.

    Seeing as how bad their CMR drives are, though, I can't even imagine how bad the SMR drives are. Maybe it would help if they put an iron wolf sticker on them like their other drives. Then it would be strong like iron and loyal like wolf.
  • takeshi7 - Tuesday, June 18, 2019 - link

    The "cold air constantly moving over them" might be part of the problem. Hard drives like to operate at warm temperatures. They're designed that way
  • takeshi7 - Tuesday, June 18, 2019 - link

    And also running shucked drives in RAID just sounds like a terrible idea.
  • Qasar - Wednesday, June 19, 2019 - link

    sounds like oRAirwolf is using hdds that aren't made for the use case he is putting them in, and they are just wearing out, and as was mentioned.. the constant cold air.. cant be good. maybe went the inexpensive way vs the slightly more expensive way just to save a few bucks ?
  • BeethovensCat - Tuesday, June 18, 2019 - link

    Are there any rumors or reliable information about WD releasing a 5Tb or 6Tb version of their Passport/Elements series drives? I have a number of 3Tb drives and they are getting too small. Have been holding on to them in the hope that there will be a 5Tb version available sometime during 2019. Has anyone heard anything. Would like to avoid the large drives with power cables etc.
  • fmcjw - Tuesday, June 18, 2019 - link

    no innovation in this area. BTW, the article, being Anandtech, should've looked into background shuttling of data across shingles, which expend precious energy to gain performance (much like a TLC SSD), but also increase wear. And how about read performance compared to non-SMR drives?
  • fmcjw - Tuesday, June 18, 2019 - link

    no innovation for about 3 years, just enclosure changes.

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