Seagate Momentus XT 750GB Solid State Hybrid Drive Review – SSD Performance With HDD Capacity


The F.A.S.T. Factor Advantage Flash Assisted Storage Technology is what makes the melding of hybrid drive worthwhile.  simply put, it is what makes the Momentus XT fast.


  • FAST Boot  Cold boot-ups within seconds of an SSD  24 seconds or faster on test systems, compared to 20 seconds for an SSD  and 75% faster than a 7200RPM drive.
  • FAST Flash  Increases data integrity and reduces wear and tear on both the NAND flash and hard disk drive.
  • FAST Read  Produces high read speeds.
  • Seagate Adaptive Memory Technology  Self-learning algorithm gives users SSD-like response on their most frequently used applications and files.

What FAST is, is a term encompassing three firmware-level features: FAST Management, Adaptive Memory Technology, and FAST Boot.


  • Flash Management – Momentus XT solid state hybrid drives also implement a management feature that provides seamless integration between hardware, firmware and high-speed NAND flash while maintaining data integrity under all conditions any system, any OS and with any driver.
  • Adaptive Memory Technology – Adaptive Memory technology delivers SSD-like response from the applications and files you use the most. It lets the Momentus XT drive selectively tackle frequently used data, copy it to the flash, track its relevancy and keep the flash current. You get the instant response experience you need to perform at your best.
  • FAST Boot -Momentus XT drives are known for incredibly fast boot-up times, and now they are even better with FAST Factor boot technology. This system boot-up technique can reduce your boot time to mere seconds for a fast cold-boot start. It can cut your system start-up time by up to 65% over a traditional HDD. FAST Factor boot technology will deliver the fastest boot possible, whether you boot your system once a day or once a week. Your OS boot-up files are always there, ready to work.

While it is unknown how exactly these features function, one thing that can be deduced is that FAST is meant to boost read performance, not write, a point clearly made using FAST Boot and Adaptive Memory Technology.

FAST Management on the other hand is responsible for handling the NAND itself. As previously stated, SLC NAND access can be disabled if the Momentus XT’s SSD portion ever break downs.

In that unlikely case, FAST management will convert the hybrid drive into a standard hard drive, keeping the data intact while only losing the SSD-like performance. The SSD bond really shows here, as traditional hard drives do not use firmware.

With all of these terms established, what about TRIM? As also mentioned previously, the Momentus XT is more of a hard drive than an SSD, with the SSD portion only making up 8Gb.  Therefore, TRIM is not available, or even possible. This makes FAST Management even more valuable as it essentially acts as garbage collection for the Momentus XT, especially since files will not be copied to the SSD/NAND segment of the hybrid drive. Think of FAST Management as Seagate’s substitute for TRIM. It does not really matter how the garbage collection works, as long as it functions and prevents degradation.

Moving on, Adaptive Memory Technology deals with blocks that remain on both the hard drive and NAND. The technology monitors and adapts to how the user utilizes the Momentus XT in every-day computing. This is one of the major contributors to the overall speed of the Momentus XT drive, a fact witnessed during testing. There was a large performance gap between programs that were launched once to the same programs being executed, for say, the tenth time. Once the Adaptive Memory Technology figures out the user’s pattern of access, it stores that information on the NAND portion of the drive. Hence, for all benchmarks, the Momentus and Momentus XT’s results reflect at least ten access executions.

Finally, FAST Boot is exactly what it reads as. After every reboot, FAST records every block that is accessed by the user, and stores that data onto the NAND.

Those who reboot and shutdown frequently will obviously see a vast improvement in performance in a shorter period of time versus those who reboot infrequently. Theoretically however, after a broader time of usage, FAST Boot should perform equally for both crowds.


  1. The m4 ssd is one of the most reliable ssd out there. the 64 gig version can be purchased now for $109 free shipping no tax from newegg add a terabyte hd for mass storage and you get a faster, higher capacity and cheaper solution!
    the 128 gig version is $199

    • You can’t fit that configuration in most laptops. This is a 2.5inch drive perfect for laptops. If space isn’t an issue you could even look at a RAID system.

      I have used the 500Gb XT for a year now and am impressed. Not just with the real world usage but in particular with Seagates commitment to sorting out the early issues with this drive. They are actually listening to these reviews taking onboard the criticism and working with its customers to progress the technology further and releasing regular updates.

  2. I think this is one of those situations where there has to be a paradigm shift in the priorities and what is being measured. A drive like this was not made to run benchmarks, it was made to learn and adapt to the usage scenario at hand. The fact that most benchmarks showed a small improvement, or no improvement at all, but the author was still raving about the product, is a testament to that. I think benchmarking the loading times of a suite of programs over consecutive runs would be a much better indicator of what this drive brings to the table. In that scenario this will probably mean the best of both HDD and SSD worlds.

    Thank you for this review and the many other informative articles. 🙂

    • Thanks, and thanks a lot for the informative post!

      While I didn’t push the fact, I was hoping readers such as yourself would figure out that there aren’t really any benchmarks that can effectively test the Momentus. I provided all of the benchmark tests one sees with essentially every drive, but they just don’t work due to the adaptive properties of the Momentus.

      Again, thank you for the insight 🙂

  3. “The SSD bond really shows here, as traditional hard drives do not use firmware.”

    Somebody needs to tell Seagate, they are distributing firmware updates to all those drives that don’t even USE firmware.

  4. Anyone notice that from the Boot Time Comparison chart that Quicktime is rubbish no matter what system you have!

  5. Thanks! A really top review. Just confirms what I thought though; that these hybrid drives are largely pointless, or at least that they’ll have a very limited lifespan. I can’t see how SSDs can cost more to produce that mechanical drives, over the long term there’s no argument for having one of these drives. As it is they still can’t compete with SSDs, but whether they compete with a setup like I have which is 128GB SSD for O/S with a 1TB IDE for storing data, I’m still largely unconvinced, particularly given their price!

  6. Different model, but I have had the Momentus XT 500GB for about a year now and it got painfully slow after six months making new slowness records each month.. Maybe it’s just me getting partially spoiled by the SSD part, but still.. Sometimes I think I must be infected with everything bad crawling the web, bots, trojans and all sort of viruses hogging my system, but I am afraid it’s just a growing feeling of slowness. When the SSD part works it’s great, but it’s too small, only 4GB on this model, and when it switch to HDD it’s horribly slow. I think all that this drive and other hybrids really do is to wet your appetite for a total HDD-free SSD solution.. Which kind of explains why I am lurking around here; I think it’s time to go fully SSD.

  7. I will be first in line to buy 2-4 Hybrid HDD/SSD 2.5″ drives when there comes a version with a combination of 32-64GB SLC NAND Flash + 1TB 7200RPM (1TB platter, single platter) HDD + 64GB ECC DRAM. I am all for using 2.5″ form-factor drives in my desktop, as I can fit a lot more drives in a relatively limited space, and to be able to have MORE drives without sacrificing speed but rather enhancing it, is a dream come true!

    WD just announced a 2.5″ Drive with 64GB NAND that looks to be a “one up” of Seagate’s Momentus XT, and if they really pan out well, I will be buying at least two to start with and throwing them into a RAID0 array. Although I have a 256GB Samsung 830 SSD, and will soon have a second, I want large-capacity storage for uncompressed audio files (tens of thousands) and 1080p video files, not to mention games. 2-4x 1TB single-platter 2.5″ hybrid drives with 32-64GB SLC NAND each would make THE fastest RAID array that actually uses spinning disks.
    We’re talking 64-128GB/128-256GB of Solid State Storage with 2-4 Terabytes of disk storage! Combined with good detection algorithms, I don’t see why it couldn’t perform so close to actual SSD’s as to be imperceptible!

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