SanDisk Z400s SSD Review

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Conclusion

SanDisk's Z400s is inferior to the products we compared it to. The drive serves up impressive notebook battery life, but that's one of its few bright spots. To be fair, in some of our other tests, the Z400s fares much better than I expected.

We recently learned that the Z400s is being validated by at least one major OEM, though it hasn't completed the process yet. We've been talking a lot about low-end SSDs displacing hard drives in tier-one PCs, so it'll be interesting to see if builders can roll DRAM-less solid-state storage into their designs before the holidays.

If we take this new class of SSD and generalize about their allure, it becomes clear that the upgrade market won't be swayed. OEMs won't be able to help but dip those three letters into gold for their marketing purpose. However, just because you see SSD on the spec sheet doesn't mean you're getting the drive you really want. As a storage reviewer, I'm a little biased. But the performance metrics show that these products are faster than hard drives and slower than the SSDs truly deserving of praise.

Price is a primary consideration in this segment. A while back, four 128GB Z400s could be purchased together for 25 cents per gigabyte. Sadly, that deal is no longer available. If that's what you pay, though, then you know OEMs are getting them even cheaper in volume. I would buy a notebook with this SSD installed, but I wouldn't pay a premium for it. Enthusiasts who value the snappy SSD experience we love at the high end will treat DRAM-less drives the same way they would a hard disk: they'd replace it.

That's not to say everyone who buys one of these in an OEM notebook will do the same thing. A DRAM-less SSD is better than a mechanical drive. But price parity will be part of the package. Just ask questions when you see a system advertised with an SSD inside to really understand what you're getting.

As a potential upgrade, the Z400s is a fairly poor prospect, largely because of its price. In terms of value, Samsung's 850 EVO just wrecks every other company's attempt to compete. With the 128GB Z400s at $45 and the 120GB 850 EVO going for $68, we have to recommend Samsung's offering. The 256GB-class comparison also favors the 850 EVO ($88 versus $80). The only way we can see this changing would be if you need to buy in volume. For upgrading a single PC, spend the extra $20 on Samsung, we say.


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Chris Ramseyer is a Contributing Editor for Tom's Hardware, covering Storage. Follow him on Twitter and on Facebook.

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Chris Ramseyer
Chris Ramseyer is a Contributing Editor for Tom's Hardware US. He tests and reviews consumer storage.
  • ZolaIII
    Would actually like to see the 240 GB model & dose it catches up at least reasonable with declared write speeds.

    Whole topic is a dead fish until we see first implementation next year that will use 3D XPoint RAM instead of DRAM for caching purposes.
    Reply
  • zodiacfml
    Nothing to see here except the OEMs who will probably save more by choosing this drive.
    Reply
  • rmszaphod
    Misread.
    Reply
  • Duken4evr
    Newegg has Adata 128GB drives on sale for $38. Deal abound out there. OEMs may buy these for cheap so they can advertise their $400 laptop has an SSD, but the rest of us smart shoppers can score deals on better drives for our upgrade purposes.
    Reply
  • Marcus Zettergren
    Part of the conclusion just doesn't make sense even though i agree the Evo is so much better.

    As a potential upgrade, the Z400s is a fairly poor prospect, largely because of its price. In terms of value, Samsung's 850 EVO just wrecks every other company's attempt to compete. With the 128GB Z400s at $45 and the 120GB 850 EVO going for $68, we have to recommend Samsung's offering.

    Unless my maths are way off, which it very well could be, the EVO is 62% more/GB. For a gaming disk, the Z400 is just as good as the EVO, and i suspect for a thin ultrabook with a "U" cpu, the cpu will be the bottleneck long before an SSD would be a showstopper.
    Reply
  • photonboy
    Marcus Zettergren,
    Gaming performance (which mainly only affects load times) is but one use case scenario. The CPU isn't going to be the bottleneck either, though low-cost notebooks can be limited by the main chipset of the motherboard, though even then it wouldn't be a total bottleneck but could limit performance.

    How the CPU, chipset, and different scenarios work isn't a simple calculation.

    I think this is GREAT to have an offering like this. I know fast SSD's seem important to most people but they way my sister uses her PC she wouldn't know the difference. It would still boot up pretty quick and then she's mostly in an office environment.

    It's a lot faster than an HDD at times, reasonably inexpensive, and won't take several seconds to come out of standby mode like an HDD.
    Reply
  • nekromobo
    If we want to push solid-state storage into lower-end systems, the expensive DRAM has to go.

    According to Anandtech this December 2015:

    The average spot price of one 4Gb DDR4 memory chip rated to run at 2133MHz was $2.221 at press time, according to DRAMeXchange,

    So for a DRAM in SSD thats 2.221$ well spend (Ok, maybe it increases cost 4$ but anyway...)
    Make it DDR3 and youll save 50cents.
    Reply
  • CRamseyer
    There is a bit more to it than just the physical DRAM. The controller has to have provisions in place for it, the extra design in the PCB, other components to support the DRAM and so on. It all adds up when companies are fighting to find a way to shave off a few Dollars at a time.
    Reply
  • photonboy
    17193485 said:
    There is a bit more to it than just the physical DRAM. The controller has to have provisions in place for it, the extra design in the PCB, other components to support the DRAM and so on. It all adds up when companies are fighting to find a way to shave off a few Dollars at a time.

    Exactly.
    Let's do some more meaningful algebra which I'm making up of course but know to be quite possible:
    1) Profit margin of laptop-> $10
    2) Savings on SSD (total) vs faster SSD-> $5

    Profit is DOUBLED!

    Most people will just see that it's an SSD and the capacity on the entry or mid-tier devices this would be aimed for. Saving $5 can make a huge difference in profits since as said they're fighting over scraps a lot of the time.

    Some mobile devices were actually just BREAKING EVEN due to the tight competition and price drops.
    Reply
  • uglyduckling81

    1) Profit margin of laptop-> $10
    2) Savings on SSD (total) vs faster SSD-> $5

    Profit is DOUBLED!

    Just tell me again how a $10 profit increased to a $15 profit is double?
    Reply