It's been over a year since I reviewed Seagate's first hybrid hard drive: the 500GB Momentus XT. At the time I felt that it wasn't nearly as good as an SSD, but likely the best 2.5" hard drive money could buy. Armed with only 4GB of SLC NAND acting as a read cache, the original Momentus XT delivered VelociRaptor performance in a much more power efficient package. 

Since then Seagate hasn't updated or expanded its line of hybrid HDDs at all. I kept hearing rumors of new drives coming but nothing ever surfaced. More recently Seagate announced that the next version of the Barracuda XT will be a hybrid drive as well.

Today Seagate is announcing availability of its second generation Momentus XT. Now at 750GB with 8GB of SLC NAND (once again, as a read cache), the new Momentus XT is a definite evolution over its predecessor. With a larger NAND cache Seagate can be more aggressive with its caching, not to mention the improvements to the mechanical side of the drive as well. The entire package is still not nearly as fast a value SSD, but it's doing much better than mechanical (3.5" included) hard drives in our tests.

Write caching is still not enabled on the NAND, however Seagate is planning on enabling it via a firmware update sometime in 2012. I've seen results from an early version of the write caching firmware and the improvement is tangible. 

The 750GB Momentus XT will be available at a MSRP of $245.

We're still hard at work on our review of the drive, expect to see it later this week!

Update: Our review is live!

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  • BernardV - Tuesday, November 29, 2011 - link

    I was in the market for one of the first generation drives about 6 months back, but during my research on the drive I went onto the Seagate forums, needless to say my mind was quickly changed about buying one of these drive. There seemed to be endless complaints about reliability?

    On another subject is 8GB read cache perhaps still not large enough? Or does it come down to prices that will skyrocket?
  • mevans336 - Tuesday, November 29, 2011 - link

    I suspect, (as Anand did back in his original article) that 8GB sufficiently increased read performance, but it's really the write cache that is going to be the killer.

    After all, for an average user, what are they going to write that is anywhere near 8GB in size?
  • iGo - Tuesday, November 29, 2011 - link

    When I bought the 500gb Momentus XT, I was literally taking up a gamble as after reading the complaints on Seagate forums I was in two minds too. But it's been running just fine in my 13" Macbook (late 2008 model) and I had kept close watch on firmware updates for the drive from Seagate. It's definitely not as fast as SSD, but the improvement is there. I always felt that 4GB cache is way too low, especially after seeing even Intel SSD caching falling short at 20GB SSD for caching lot of content.

    Although I've to say, that after using my GF's 11" macbook air, I really feel my 13" macbook with better processor is still dog slow thanks to the mechanical drive. But then I just focus my mind on how my friends' laptops are even slower with 5400RPM and even 7200RPM drives and it makes me love the Momentus XT drive in mine. :)
  • mwarner1 - Tuesday, November 29, 2011 - link

    I bought a 500GB XT when it first came out to replace the internal 5400rpm 250GB of my 11.6" CULV netbook. I could not justify a huge SSD in such a machine for cost reasons (I need at least 250GB) and thought this would be an ideal compromise.

    I have also read of the issues with the drive over at the Seagate forums, but have never had any issues worth noting myself. It certainly does not offer the performance of an SSD, but is a notable, if fairly small, step up from a standard 7,200rpm drive and a marked improvement over the 5,400rpm drives that ship with pretty much all laptops & netbooks.

    I doubt I will be upgrading to this larger capacity drive myself, but I can certainly recommend the XT line for laptop users who only have one drive bay and require a reasonable capacity, which is likely the majority of the market these days?
  • TrackSmart - Thursday, December 1, 2011 - link

    In some laptops you can swap the optical drive for a second hard disk or SSD. It's a nice compromise, since you can purchase a cheap 64 GB SSD and still have the HDD for extra storage. Not useful for your laptop, which lacks an optical drive.

    I'm guessing that it won't be long before you'll see a single-drive-bay solution that mimics the above. Heck, if I had the means, I'd produce this myself. In my simplified world, all you'd need to do is mount a RAID controller and the SSD chipset/NAND onto a small board and combine this with a low profile hard disk (i.e. single platter 320GB or 500 GB drive). Are there any venture capitalists out there ready to fund this project for me?
  • kmmatney - Tuesday, November 29, 2011 - link

    The problem with forums is that you will only see people who have problems. I've had no problems at all with my 500GB XT, and I know a few other people who haven't had any issues either.
  • Operandi - Tuesday, November 29, 2011 - link

    If Seagate wanted these drives to be relivent they have to move a hell of a lot faster than this. This drive should have been out 12 months ago, and we should have a 1TB (and higher 3.5" drives) with 16GB of NAND cache as well as write caching. At this point does anyone care about something like this?
  • kyuu - Tuesday, November 29, 2011 - link

    I absolutely do. Though I'm more interested in the Barracuda XT hybrids since I don't really use a laptop, I would definitely use a hybrid drive as my mass storage drive over a traditional HDD along with my primary SSD (since I also store applications that I can't fit on my relatively small SSD that can still benefit from increased IO performance). And, I would still recommend the Momentus XTs to anyone I know who uses a laptop and isn't going to spend a couple hundred dollars for a much smaller SSD drive. I'd also love to use one of these for a PS3/Xbox 360 HDD.

    The reliability issues you see on the forums are the minority complaining loudly. The people who have no issues don't generally pop into the forums to report everything working smoothly. I've been using the 500GB Momentus XT in my desktop rig as my secondary HDD for a quite a while now with nary a hiccup.

    I do hope it's cheaper than the MSRP. If HDD prices in general don't relatively quickly, I don't know if they'll be able to price these cheap enough to be competitive.
  • stopclips - Tuesday, November 29, 2011 - link

    I care. I'm an electronic musician and I've wanted to get one for my touring laptop, however 500GB doesn't cut it for media storage for me. 750GB will suffice just fine. I'm looking forward to the review.
  • FaaR - Tuesday, November 29, 2011 - link

    Why not just keep your media on a portable USB drive? There's 1TB 2.5" units today (or maybe more) that run bus powered. You don't need fancy flash caching for music data, when a dog-ass slow CD drive from the early 1980s can deliver uncompressed music data just fine a regular mechanical drive serving MP3 or whatever will suffice just fine. :)

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