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Seagate Momentus XT review: Seagate Momentus XT

Seagate Momentus XT

Dong Ngo SF Labs Manager, Editor / Reviews
CNET editor Dong Ngo has been involved with technology since 2000, starting with testing gadgets and writing code for CNET Labs' benchmarks. He now manages CNET San Francisco Labs, reviews 3D printers, networking/storage devices, and also writes about other topics from online security to new gadgets and how technology impacts the life of people around the world.
Dong Ngo
5 min read

The Seagate Momentus XT is the ideal choice for those who have been searching for a hard drive that offers the performance of a solid state drive without the premium price. With a street price of around at $135 for the 500GB version, the Momentus XT is just a fraction of the cost of an SSD, and delivers more capacity for your dollar.


Seagate Momentus XT

The Good

The Seagate Momentus XT offers excellent performance at a price that's significantly lower than solid state drives (SSDs). It offers a larger capacity than SSDs and comes with a generous five-year warranty.

The Bad

When compared with traditional hard drives, the Momentus XT is more expensive and currently caps at 500GB. The drive doesn't support the new SATA 6Gbps data transfer rate.

The Bottom Line

The Momentus XT is an excellent replacement for traditional laptop hard drives. It offers large capacities and SSD-like performance at a fraction of the cost.

Compared with conventional hard drives, the Momentus offers a significant boost in performance by incorporating 4GB of flash memory. The new hybrid hard drive has a built-in algorithm that automatically relocates frequently accessed data on the flash memory area, therefore boosting the device's overall performance over time.

Though about 50 percent more expensive than traditional high-speed 2.5-inch hard drives of the same standard and capacity, we found that the Seagate Momentus XT is worth the investment for its added performance.

Design and features
The Momentus XT hard drive looks exactly like a traditional SATA 2.5-incher that you can find inside most laptop computers. The drive is 9.5mm thick, making it suitable for the widest selection of mobile applications.

On the inside, however, the drive is an entirely new beast. It is the first mass production hybrid hard drive that uses both flash memory and the traditional hard-disk platters for its storage. Seagate says that the Momentus XT features an embedded algorithm, called Adaptive Memory technology, that automatically moves frequently used information into the flash memory for faster access.

In our trials, this technology actually worked. For example, it took our test system, which used a Momentus XT as its main hard drive, the third boot time to consistently boot faster than the first time. Other test applications generally show improvement after using them the second time.

The Adaptive Memory technology is a built-in feature of the hard drive, so it works independently from the operating system. There's no driver or software needed to take advantage of this feature.

The Momentus XT supports SATA II (3Gbps). Unfortunately, it doesn't support the newer and faster SATA III (6Gbps). Currently there's no 2.5-inch hard drive that supports this new standard, however.

Apart from the 4GB of flash memory that's nonmovable, the hard drive's platter spins at 7,200rpm; most laptop hard drives spin at 5,400rpm. It also has 32MB of cache memory, which is higher than most drives of its size. It doesn't, however, offer the other benefits of a true SSD, such as durability and saving energy.

The Momentus XT works exactly like any other traditional SATA 2.5-inch hard drive. We tried installing a few different operating systems with it and ran into no problems. The drive will work with any applications where existing traditional hard drives of the same SATA standard are used.

Cost per gigabyte
The Momentus XT is more expensive in terms of dollars per gigabyte compared with other, traditional drives. Compared with SSDs, even those that offer much less storage space, the Momentus XT is truly a bargain: for the 500GB version, you'll have to pay just 27 cents per gigabyte. One of the most affordable SSDs on the market, in terms of cost per gigabyte is the 120GB Patriot Warp V.2 , and it costs almost ten times as much, at $2.57 per gigabyte.

In addition, you won't be able to find an SSD that offers up to 500GB of storage space. And if you could, you probably wouldn't be able to afford it.

We tested the drive thoroughly with many different applications and were impressed by its performance. Apart from the throughput test, which focuses on drive performance alone, all other tests are designed to gauge the computer's performance as a whole; the hard drive only plays a small role in the final score. In all tests, we were able to see the difference the Momentus XT made.

We tested the Momentus against three other SATA 3Gbps hard drives: a 3.5-inch WD VelociRaptor (300GB, 10,000rpm), a 2.5-inch Fujitsu MHV2120BH (120GB, 5,400rpm), and a 3.5-inch WD Caviar SE16 (500GB, 7,200rpm). For each hard drive, the test system was reimaged with exactly the same operating system, system settings, test software, and data.

In the boot time test, where we time how long it takes for the computer to boot using the test hard drive as its main hard drive, the Momentus took only 12.1 seconds; the other three took between 20 and 28 seconds.

In the multimedia multitasking test, the Momentus XT did very well, taking only 730 seconds, even faster than the VelociRaptor, which took 769 seconds. It also did very well with the Cinebench test, trailing just behind just the VelociRaptor.

In the throughput test, where we copy a large amount of data from one place to another from within the test computer's main hard drive, the Momentus XT did really well, registering 39.91MBps, even faster than the 30.25MBps of the Intel X-25M SSD.

The Momentus XT exceeded our expectations when it comes to performance. It's arguable the fastest 2.5-inch SATA hard drive on the market.

System performance (in seconds)
(Shorter bars indicate better performance)
Boot time  
Fujitsu MHV2120BH
WD Caviar SE16
WD VelociRaptor
Seagate Momentus XT

(Longer bars indicate better performance)
Seagate Momentus XT
Fujitsu MHV2120BH

Data transfer (in MBps)
(Longer bars indicate better performance)
Seagate Momentus XT
Intel X-25M
Fujitsu MHV2120BH

Find out more about how we test hard drives.

Service and support
When it comes to storage devices, the length of the warranty is the most important factor and Seagate delivers. The company backs the Momentus XT with a generous five-year warranty. At the company's Web site, you'll find a comprehensive list of forums, knowledge bases, driver downloads, installation help, and FAQs to help you troubleshoot your drive. Phone support is also available via live chat, e-mail, and phone, from 6 a.m. to 8 p.m. weekdays.