In a move I honestly never thought would happen, Seagate is announcing today plans to brings its 5mm 2.5" Laptop Ultrathin HDD to Android tablets. The drive will come as a part of Seagate's mobile enablement kit and offered to OEMs looking to cost effectively scale tablet storage beyond what's realisticaly possible with NAND alone.

Seagate's reference design still includes a small amount of NAND (8GB) on the tablet in addition to the 500GB Ultra Mobile HDD. The HDD itself has been modified to include an additional gravity sensor, making the drive a bit more robust as the physical usage model with a tablet can be a bit more intense than a traditional notebook. The mobile enablement kit also includes Seagate's Dynamic Data Driver for Android, effectively an SSD caching layer. The combination of NAND flash and Ultra Mobile HDD will present themselves to the user as a single volume, with the Dynamic Data Driver choosing what data to keep on NAND and what to keep on the HDD. The driver also communicates sensor data from the tablet to the HDD itself, allowing it to better prepare itself in the case of a drop.

One of the reasons for the current success of modern day tablets and smartphones is because they don't rely on mechanical storage, which can deliver a poor user experience for random (or pseudo-random) accesses that are common in client workloads. As is the case with all NAND caching solutions, success is  really a matter of the OEM putting enough NAND on board to effectively cache everything but large media transfers. In the PC space, we don't see a lot of that, but in tablets where the amount of NAND you need is pretty small to begin with I feel like there's more of a chance of this not being horrible. Peak sequential performance from the Ultra Mobile HDD is around 100MB/s, making it better than most eMMC solutions in tablets today. Random IO is obviously the problem, but a properly sized cache should help make sure most random requests are serviced by the NAND in the system.

There are other downsides of course. Although Seagate's Ultra Mobile HDD is only 5mm thick, it's still a 2.5" drive - which does eat up valuable real estate inside a tablet. Battery life can also be affected. Seagate claims no impact on battery life since the Dynamic Data Driver can spin the HDD down when it's not in use, but when the drive is in use you're looking at a power penalty of 500mW to 1.4W. That's about the range of power consumption (idle to web browsing) for the entire SoC in the 2013 Nexus 7.

Overall it's an interesting idea but one that I don't expect to gain tons of traction, at least not in traditional Android tablets. In convergence devices, maybe. Perhaps the bigger question here is: what does the future of mechanical storage look like in ultraportable client computers? Our recommendation for years now has been SSD + large HDD if you can fit them both, otherwise just an SSD + external/cloud storage. Do you guys see the market, particularly cost sensitive portions of it, evolving any differently?

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  • CZroe - Wednesday, September 11, 2013 - link

    "4. You can be a little rough on the device, like tipping it over accidentally, and not worry about head crash."
    That's precisely why this new product integrates with the mobile device's sensors. It's a lot more intelligent than a simple laptop HDD's drop sensor. For example, it can err on the side of caution more readily if there is no touch contact with the screen and the orientation has changed since it was last touched (upside down).
  • eanazag - Wednesday, September 11, 2013 - link

    Agree. I would just aim for a 256 GB SSD - which already exists - for the next couple years in the Surface Pro. The 64 GB model is just dumb. The 128 GB is a tight squeeze and I have a 64GB microSD plugged in.

    I would use this with a thin SSD plugged into the same slot. I won't go SSD-less. Think about laying this like two pancakes into a laptop with SSD and thin HDD in the same slot where just one hard drive used to fit. That would be a compromise I 'd go for.
  • XZerg - Monday, September 9, 2013 - link

    I wouldn't mind something like this in say Surface pro style or "pc" tablets but with a beefier ssd to pair with till ssd prices at that size (storage) do not cost more than rest of the components or even relatively up there. this has no place in android/ipad size tablets as there are plenty of better options in terms of performance, power and physical size (not storage) and dimensions out there already. Also the growing trend is moving towards "NAS" storage while keeping only more regularly used data on tablets.
  • mrdude - Monday, September 9, 2013 - link

    I can definitely see a market for these, Anand. For example, people who want to spend loads of money on a device with 500GB of mechanical storage and watch as the platters shatter when they're playing one of those 'jitter your device for this action' games. There's nothing quite as thrilling as that feeling of watching your >$600 tablet-thing-a-majig rendered useless in your loving arms. It'll be like shaken baby syndrome only with more crying.
  • Flunk - Monday, September 9, 2013 - link

    I could see this being used in tablets like the Surface Pro. Windows tablets are always screaming for more space. But for standard Androids or iPads it's just too big, too heavy, too much power and probably too much money too. Plus the performance in Android would be terrible, the entire OS is designed around having flash-speed random storage access. It's really the biggest reason people buy tablets.
  • MrSpadge - Monday, September 9, 2013 - link

    If it's well done the HDD won't be needed very often - in this case it should be perfect for value-conscious buyers. Increase the cache to 16 GB and anything but videos and large music collections should fit in the NAND. People paying 100 bucks more for an iDevice with 32 GB more NAND would look rather stupid in comparison.

    I could also see a market for hybrid storage in tablets where you put an HDD into the keyboard dock (along with some battery and maybe WLAN for remote access).
  • lmcd - Monday, September 9, 2013 - link

    Very appealing indeed -- glad someone sees it.
  • Death666Angel - Monday, September 9, 2013 - link

    Sounds like something very niche. I expect some Archos products to use it, but the general tablet market has been happy with 16 to 32GB onboard and expandability with mSD cards. There are just too many downsides to this, at least in the ARM tablet space. On Win8 with Atom+ CPUs, there may be more positives to outweigh the negatives.
  • psuedonymous - Monday, September 9, 2013 - link

    I was about to mention Archos, who've been putting HDDs into tablets (recently Android, previously their own OS) for years.
  • Rick83 - Monday, September 9, 2013 - link

    I wonder how one can cover this kind of announcement without name-dropping Archos :D

    Their 5" Android Tablet with 500 GB came out....4 years ago now? And had a small but dedicated following for quite some time, simply because it was basically the only choice if you needed that amount of storage.

    Plus, with the G9 I think they also paired it with a flash-cache, so really, they've done exactly what the article announces, two years ago. A bit of an oversight not to mention it....

    Of course, since then Archos have changed their game a bit, so I'm not sure if they've pre-ordered the first batches, or just go after the mass market now.

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