Seagate Momentus XT (500GB)

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.

CNET Rating
User Rating

View more from Seagate »

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 AU$120 for the 500GB version, the Momentus XT is just a fraction of the cost of an SSD, and delivers more capacity for your dollar.

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.

Although it's about 50 per cent 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.

Swirling yellow magic beams not included.
(Credit: Seagate)

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, which 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 non-movable, the hard drive's platter spins at 7200rpm; most laptop hard drives spin at 5400rpm. 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 we 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 US$0.27 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 10 times as much, at US$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 that 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, 5400rpm) and a 3.5-inch WD Caviar SE16 (500GB, 7200rpm). For each hard drive, the test system was re-imaged with exactly the same operating system, system settings, test software and data.


(Longer bars indicate better performance

  • WD VelociRaptor
  • Seagate Momentus XT
  • WD Caviar SE16
  • Fujitsu MHV2120BH
  • Longer bars equal better performance 4,838 4834 4830 4759

Data transfer (in Mbps)

(Longer bars indicate better performance

  • WD VelociRaptor
  • Seagate Momentus XT
  • WD Caviar SE16
  • Fujitsu MHV2120BH
  • Longer bars equal better performance 40.45 39.91 22.7 12.16

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 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 came to performance. It's arguable that it's the fastest 2.5-inch SATA hard drive on the market.


Add Your Review 1

* Below fields optional

Post comment as
PhilippaP Facebook

"Definately a better choice than 5400rpm or 7200rpm"

PhilippaP posted a review   

The Good:Much faster than standard drives (over time)

The Bad:salespeople have no idea how to sell these and they're actually slower at first

I've been using one of these all year on my Macbook. I had a couple of 7200rpm drives but wanted to see the difference with a Hybrid. The sales people had no idea, it was like "yeah, well, they're supposed to be real good". Great selling pitch, not! And I paid $189 in January for the 500gb.
But I figured at worst it would be as fast as the 7200's. So I cloned my existing 7200 and installed the Hybrid.
I wasn't happy. Not only was it not faster (I timed it) than the 7200 drive but it was actually slower! I got back to the sales guys which was a total waste of time and did a bit of surfing to find out if I'd received a dud.
Eventually after not finding out much at all I noticed it was getting a little faster each time I booted up. If only I had known about the Adaptive Memory Tech, or sales staff had known, I could have saved myself a heap of angst.
When I first timed it my 7200 would boot up in 57 seconds, and the first time I booted the Hybrid up it took 2mins 5secs. After using it for a while it would consistently boot Snow Leopard in 37 seconds. In Lion it boots in 43seconds.....but that's improving by tiny degrees as time passes.
So that's my experience with them. I'm pleased they're getting cheaper because now I'll buy one for my Asus.
Can anyone suggest a reliable, free, Windows clone? :D

Sponsored Links
CNET's latest

User Reviews / Comments  Seagate Momentus XT (500GB)

  • PhilippaP



    "I've been using one of these all year on my Macbook. I had a couple of 7200rpm drives but wanted to see the difference with a Hybrid. The sales people had no idea, it was like "yeah, well, they'r..."

CNET Speedtest

Recently Viewed Products