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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  • bmbw2014 - Monday, September 9, 2013 - link

    Technically wise this is brilliant but I wonder how much operating noise will affect the casual user experience of a tablet? Do they compensate by reducing RPM?
  • retrospooty - Monday, September 9, 2013 - link

    Technically wise this is possible, but I wonder how many design wins they actually have. Making a product like this is one thing, but making it doesn't mean OEM's are knocking on the door trying to put it into their devices. I would be absolutely amazed if we see this in more than a few niche tablets. Certainly not in any popular model.
  • Cow86 - Monday, September 9, 2013 - link

    I thought almost all mobile HDD's were already at 5400 RPM nowadays? Shouldn't be a huge noise concern I expect...still of course infinitely noisier than a silent SSD though.

    I too don't expect this to gain huge traction with the power consumption and other issues in a small tablet, but the option might work for it's good it's being offered.
  • bobbozzo - Monday, September 9, 2013 - link

    Some laptop drives have been 4200RPM. I've got one, but it is at least several years old. Terribly slow too.
  • StormyParis - Monday, September 9, 2013 - link

    I want as much storage as possible on my mobile devices, because
    - when I'm on the move I can't count on being connected
    - when I *am* connected it is usually too slow
    - and too expensive
    - and unreliable
    - and that's when I most need my stuff, either to work or to relax.

    Right now, I've got a netbook with a 1TB HD that I carry around when I'm going away for more than a week-end. Wifi hard drives don't cut it (pitiful battery life, high price). Micro-SD cards are still limited to 64GB (I've got 5-6 of those already...)

    So yep, I'm interested. Especially if the drawbacks (fragility, size, price, battery, noise, performance...) are contained.

    This sound all the more interesting for the Win8 tablets that purport to replace laptops.
  • lmcd - Monday, September 9, 2013 - link

    Yeah, well RT needs to trim down though, I'd like to see it near the size of a smartphone OS outside of things like recovery partitions. The OS and 1-2 GB app space should fit into the 8GB cache in my opinion.

    And both platforms need to manage this space much better than will be handled forseeably.
  • CZroe - Monday, September 9, 2013 - link

    "I honestly never thought would happen..."
    This is obviously intended for things like Surface Pro 2 and Razer Edge Pro gaming tablet, where I kinda expected something like this (both x86). Also, super-thin notebooks can use it as a hybrid SSD/HDD. Imagine an Ultrabook version of an Alienware M11x!
  • jeffkibuule - Monday, September 9, 2013 - link

    One look at the Surface Pro tear down on iFixIt will tell you there is absolutely no space for such a drive.
  • CZroe - Wednesday, September 11, 2013 - link

    Do you realize how thin this is? Of course it will not fit in a tablet that wasn't designed for it, but a PCB designed around it in a Surface 2 or Razer Edge Pro 2 would be easily possible, especially with the SSD integrated, Haswell, and other advancements.
  • meacupla - Monday, September 9, 2013 - link

    If you actually own a surface pro, you wouldn't want an HDD in it.
    1. HDD is heavier than mSATA
    2. eats into already precious little battery life
    3. HDD is slower, even if it is a hybrid.
    4. You can be a little rough on the device, like tipping it over accidentally, and not worry about head crash.
    5. USB3.0 2TB portable external and 64GB microSD can augment storage plenty.

    Now, if the HDD is inside a separate keyboard and battery dock, like transformer book, then why not?

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