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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  • mkozakewich - Monday, September 9, 2013 - link

    You ended up missing an interesting concept: What if we could swap 5mm SSDs into such devices? Look at how those numbers compare with the speed and cost-per-GB of common eMMC. We're usually paying far more than $1/GB for extra eMMC in today's tablets, for very little performance.
  • alexvoda - Monday, September 9, 2013 - link

    There is some interesting potential for these drives.
    Since they are 5mm tall you can almost fit two of them in the space of a normal 2.5" laptop drive.
    With these you could have RAID 1 redundancy in the space usually occupied by a single drive.
    But I don't think we might see such a laptop.
  • nerd1 - Monday, September 9, 2013 - link

    I'd rather carry a portable NAS (there are a lot available now ) rather than carrying a device around with fragile mechanical drive.

    OR most android devices support OTG so you can just connect the HDD via usb directly.
  • Hubb1e - Monday, September 9, 2013 - link

    The people that don't understand this move are clearly not forward looking people. As tablets gain performance and quickly become the go-to device for computing, a tablet with a decent sized hard drive becomes increasingly appealing. In the next 5 years you're going to see people completely ditch their traditional PCs in favor of tablets with either a dock and external screen, or at least a detachable keyboard. The tablet will become the primary computing device for a large portion of the population and with that comes the need to store local images and videos. Cloud storage may work for some, but others want that content with them locally due to slow internet connections, privacy, complexity, or peace of mind.

    As soon as tablets can match the speed of a core 2 duo at 2ghz, then average users can do everything they want to do on their tablet, and whether this is on a surface pro 2 running the full x86 version of windows 8 or 9, on a Atom based x86 tablet, on windows RT, or on a traditional tablet OS, there's certainly a market for being able to store all your content locally and I think this combined with 8GB of flash is a great solution to that problem. And traditional harddrives have proven reliable in plenty of HD based iPods such as the Classic so there's little need to worry about smashing the platters unless you're throwing it against a wall.
  • meacupla - Monday, September 9, 2013 - link

    but tablets already do beat C2D 2ghz easily.
    For reference, i5-3317u is about equal in performance to a core2quad.
  • Hubb1e - Tuesday, September 10, 2013 - link

    Obviously I'm talking about mass market ARM based tablets except where I specifically reference the Surface pro. I just did a test between my old Athlon64 single core at 2.4ghz and a Samsung S4 with the snapdragon 600 at 1.9ghz and the single core Athlon was still about 2X faster than that quad core.
  • meacupla - Monday, September 9, 2013 - link

    I think these drives would be ideal inside a NUC or BRIX, if there was a provision to fit them at all.
  • BrazenRain - Monday, September 9, 2013 - link

    Couldn't an accelerometer be used as the drop sensor instead?
  • nerd1 - Monday, September 9, 2013 - link

    Drop sensors ARE accellerometers and has been used for years already.
  • Azethoth - Monday, September 9, 2013 - link

    The thing I was missing most in my tablet experience is the insane slowness of an HDD. Way to cover my needs for a retro computing experience!

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