2.5″ Serial ATA hard drive round-up

Serial ATA and NCQ are relatively new to the laptop world, and 7,200-RPM spindle speeds and high-capacity platters are still pretty cutting-edge for the 2.5″ mobile form factor. The question, of course, is how well the latest Serial ATA notebook drives have integrated these new features and capabilities. It’s also worth asking whether there’s really a big performance gap between 5,400- and 7,200-RPM notebook drives. To find the answers, we’ve assembled the latest 5,400- and 7,200-RPM Serial ATA notebook drives from Hitachi and Seagate and run them through the wringer. Read on for the surprising results.

A two-pair of mobile Serial ATA drives

2.5″?
The size and weight of traditional 3.5″ desktop hard drives are obviously a little much for mobile applications, so laptop drives have their own 2.5″ form factor. 2.5″ actually refers to the width of a mobile drive’s platter; In reality, 2.5″ drives are typically 2.75″ wide, 0.37″ tall, and 3.96″ long. That’s tiny when compared with 3.5″ desktop drives, which typically measure 4″ wide, 1.03″ tall, and 5.79″ long. Mobile drives are nearly six times smaller than their desktop counterparts by volume, and looking at the drives side by side, it’s easy to see the disparity.

A 2.5″ Serial ATA drive dwarfed by its 3.5″ counterpart

These smaller dimensions also allow 2.5″ drives to be much lighter than desktop drives, which is an important consideration for mobile applications. Typical desktop drives weigh in at over half a kilogram, but the mobile drives we’ll be looking at today are around 115g—roughly one fifth the weight. Lower weight helps mobile 2.5″ drives sip less power, too, saving on all-important battery life. Perhaps most importantly, though, the 2.5″ form factor’s smaller platters are more resistant to physical shock. That’s especially important for those of us who tend to toss laptops around with not nearly enough regard for the spinning mechanics inside.

Look familiar?

Despite their diminutive form factors, 2.5″ Serial ATA hard drives actually use the same connectors as their desktop counterparts. These drives plug into standard SATA data and power cables, making them particularly intriguing options for small form factor systems. If enthusiasts are going to press mobile Pentium M and Turion 64 processors into action in toaster-sized boxes, they might as well bring along mobile hard drives to match.

Unfortunately, the connector compatibility enjoyed by 2.5″ SATA hard drives doesn’t extend to mobile ATA drives. Those drives require pin and power adapters to work with desktop ATA systems, which isn’t quite as convenient.

The drives
Apart from Seagate’s new Momentus 5400.3, which is the first 2.5″ drive to use perpendicular recording technology, mobile drives from competing manufacturers are quite similar to one another. Unfortunately, the Momentus 5400.3 is ATA-only, so it can’t play in this Serial ATA roundup. Look for more in-depth coverage of that drive around here soon.

Since 2.5″ Serial ATA drives don’t differ much in terms of features and form factor, we have to bust out the spec sheets to see how they compare on paper. We’ve compiled the essential specs for Seagate’s Momentus 5400.2 and 7200.1 models, as well as Hitachi’s Travelstar 5K100 and 7K100 families, below. Most of the specs line up, making comparisons easy. However, hard drive manufacturers don’t always make the same information available.

2.5″ mobile drives don’t yet support 300MB/s Serial ATA transfer rates, so all the drives we’ll be looking at today top out at 150MB/s. The faster Serial ATA interface really only benefits burst transfers, so the fact that it’s missing shouldn’t be a big concern.

Unfortunately, Hitachi and Seagate disagree on how to communicate the internal transfer rates of their mobile drives. Seagate prefers to give the average sustained transfer rate, which is measured at the middle of the disk. Hitachi’s data sheets, on the other hand, give the media transfer rate. This is the transfer rate for the highest density, furthest outer-diameter zone, so it’s more of a best-case scenario. Obviously, it’s impossible to compare the Momentus drives’ average sustained transfer rates to the Travelstars’ media transfer rates, but the numbers are useful for comparing 5,400 and 7,200-RPM drives from each manufacturer.

Reporting spindle speeds is something both Hitachi and Seagate can agree on, but seek times are another story. Seagate gives the seek times for its Momentus drives as an average, but Hitachi breaks the seek time down into read and write components. Oddly, though, Hitachi quotes an average seek time for its Travelstar 5K100 but not for the 7K100. Regardless of how they’re reported, seek times look pretty consistent between the Hitachi and Seagate drives. The 5,400-RPM drives obviously have much slower seek times due to their slower spindle speeds, and that will invariably impact performance.

Platter size can also have an impact on performance, as platters with higher areal densities allow more data to be accessed over a shorter physical distance. Seagate can claim a density advantage here, as it’s the only one with 60GB platters. Those platters are only available on the Momentus 5400.2, though, and then only on certain models. The platter size for 7,200-RPM drives from both manufacturers tops out at 50GB, although again, it depends on the total capacity of the drive.

Moving to acoustics, there’s actually little difference between the idle and seek noise levels quoted by Hitachi and Seagate. We’ll be doing our own noise level tests to see which drives prove quieter in the real world. Power consumption will be tested, as well, although based on the drive specs, it’s likely there will be little difference between the drives.

Speaking of little difference, all four drives we’ll be looking at today support Native Command Queuing and have 8MB of cache. Warranty coverage differs between the two manufacturers, though. Like all Seagate drives, the Momentus 5400.2 and 7200.1 are covered by a five-year warranty, while the Hitachi drives are only covered for three years. That’s a pretty significant difference, but it’s important to note that longer warranty coverage doesn’t necessarily mean that Seagate’s drives will be less failure-prone than Hitachi’s.

For all you storage fetishists fans, we’ve snapped a few pictures of the drives. Note that there’s little physical difference between the 5,400- and 7,200-RPM drives from each manufacturer.

Hitachi’s Travelstar 5K100 (left) and 7K100 (right) from above…

And below

Seagate’s Momentus 7200.1 (left) and 5400.2 (right) from above…

And flipped

Test notes
We’ll be comparing the performance of Hitachi’s Travelstar 5K100 and 7K100 with that of Seagate’s Momentus 5400.2 and 7200.1. We’ve also thrown in a 7,200-RPM 3.5″ desktop drive for reference, although it’s obviously not in the same league as the mobile drives. Still, it will be interesting to see how its performance compares across a wide range of applications, as well as in terms of noise levels and power consumption.

These drives differ when it comes to external transfer rates, spindle speeds, platter densities, and capacity, all of which can have an impact on performance. Keep in mind the following differences as we move through our benchmarks:

On the 7,200-RPM front, the Hitachi and Seagate drives should be pretty comparable, as they share the same platter size and similar pricing. Things aren’t as pretty among our 5,400-RPM drives, though. Hitachi wasn’t able to get us its highest capacity 100GB Travelstar 5K100, so an 80GB drive has to stand in its place. The 80GB drive uses lower capacity 40GB platters that will inevitably have slower transfer rates, especially when compared with the Momentus 5400.2’s 60GB platters. Keep that in mind if you see the Momentus 5400.2 running away from the Travelstar 5K100. Also keep in mind the rather large difference in price between those two drives.

This comparison focuses on 2.5″ drive performance, so we’ve only included one desktop-class 3.5″ drive for reference. However, all testing was conducted on the same platform as our 3.5″ hard drive reviews, so you can compare the performance of our mobile drives with a wider range of 3.5″ drives by flipping back to our recent Western Digital Raptor X review.

Our testing methods
All tests were run three times, and their results were averaged, using the following test system.

Our test system was powered by OCZ PowerStream power supply units. The PowerStream was one of our Editor’s Choice winners in our last PSU round-up.

We used the following versions of our test applications:

• WorldBench 5.0
• Intel IOMeter v2004.07.30
• Xbit Labs File Copy Test v1.0 beta 13
• TCD Labs HD Tach v3.01
• Far Cry v1.3
• DOOM 3
• Intel iPEAK Storage Performance Toolkit 3.0

The test systems’ Windows desktop was set at 1280×1024 in 32-bit color at an 85Hz screen refresh rate. Vertical refresh sync (vsync) was disabled for all tests.

All the tests and methods we employed are publicly available and reproducible. If you have questions about our methods, hit our forums to talk with us about them.

WorldBench overall performance
WorldBench uses scripting to step through a series of tasks in common Windows applications. It then produces an overall score. WorldBench also spits out individual results for its component application tests, allowing us to compare performance in each. We’ll look at the overall score, and then we’ll show individual application results alongside the results from some of our own application tests.

Despite its 1,700RPM spindle speed disadvantage, the Momentus 5400.2 manages to match the overall WorldBench score of the Travelstar 7K100. That’s an impressive result for Seagate, whose Momentus 7200.1 scores an additional two points higher. The Travelstar 5K100 doesn’t fare so well, languishing three points behind its closest competition.

It’s a little surprising to see the 5,400-RPM Momentus match the 7,200-RPM Travelstar, but this is only WorldBench’s overall score. Let’s break that score into individual application test results to see how things shake out.

Multimedia editing and encoding

MusicMatch Jukebox

Windows Media Encoder

Adobe Premiere

VideoWave Movie Creator

Neither MusicMatch Jukebox nor VideoWave Movie Creator shows much performance difference between the mobile drives, but Premiere is another story. There, the Momentus 7200.1 leads the way, followed closely by the 5400.2 The 7,200-RPM Travelstar trails the 5,400-RPM Momentus by a pretty significant margin, as neither Hitachi drive seems to be particularly fast in this test.

Image processing

Adobe Photoshop

ACDSee PowerPack

The tables turn briefly in Photoshop, as the Travelstar 7K100 takes the lead. This time it’s the Momentus 7200.1 turning in a disappointing performance, although scores are pretty close overall.

Scores aren’t that close in ACDSee, though. The Momentus drives move back to the front of the 2.5″ field, and again, we see the 5400.2 edging ahead of the Travelstar 7K100.

Multitasking and office applications

Microsoft Office

Mozilla

Mozilla and Windows Media Encoder

Scores are reasonably consistent across WorldBench’s multitasking and office tests, with only a few seconds separating our mobile drives. Not even our 3.5″ desktop drive can distance itself here.

Other applications

Winzip

Nero

Both WinZip and Nero give our drives plenty of opportunity to differentiate themselves. WinZip seems particularly partial to spindle speed, with the Travelstar 7K100 just edging out the Momentus 7200.1. Seagate gets a little revenge among the 5,400-RPM drives, though, as the Momentus 5400.2 has a comfortable cushion over the Travelstar 5K100.

Unlike WinZip, Nero doesn’t discriminate on the basis of spindle speed alone. The 7,200-RPM Momentus does lead our mobile drives, but again, we see the 5400.2 ahead of what should be a faster Travelstar 7K100. At least the 7K100 is faster than the 5K100, which really struggles in this test.

Boot and load times
To test system boot and game level load times, we busted out our trusty stopwatch.

Seagate rules our boot time test, as the Momentus drives take the system to the Windows desktop at least four seconds faster than the Travelstars. Again, the 5400.2 defies conventional logic as it outpaces Hitachi’s 7,200-RPM drive.

The Momentus 5400.2’s spindle speed catches up with it in our level load tests, though. There, it proves slower than both 7,200-RPM drives by a couple of seconds. It is a little faster than the Travelstar 5K100, though, particularly in DOOM 3.

File Copy Test
File Copy Test is a pseudo-real-world benchmark that times how long it takes to create, read, and copy files in various test patterns. File copying is tested twice: once with the source and target on the same partition, and once with the target on a separate partition. Scores are presented in MB/s.

FC-Test uses five different test patterns, which gives us a good range of scores to explore. File creation speeds are pretty varied, too, with the Travelstar 7K100 leading our 2.5″ drives through the Windows and Program test patterns and the Momentus 7200.1 taking the lead in the MP3, ISO, and Install test patterns. The performance of our 5,400-RPM drives is even more interesting, as the 5400.2 is able to nip the 7K100 in a couple of test patterns and stay ahead of the 5K100 throughout.

Hitachi finds some redemption with FC-Test’s read tests, though. The 7K100 proves faster than the Momentus 7200.1 in each test pattern, and the 5400.2 isn’t even close. The 5,400-RPM Momentus does prove faster than the 5K100 across each test pattern, though.

The Momentus drives are right at home with FC-Test’s copy tests, which combine read and write operations. Overall, the 7200.1 is the fastest of our 2.5″ drives, followed closely by the 7K100 in three of five test patterns. However, in the remaining two test patterns, the 5400.2 is able to sneak ahead of the 7K100 for an upset.

iPEAK multitasking
We recently developed a series of disk-intensive multitasking tests to highlight the impact of command queuing on hard drive performance. You can get the low-down on these iPEAK-based tests here. The mean service time of each drive is reported in milliseconds, with lower values representing better performance.

Spindle speed rules in the first of our iPEAK tests, with the 7,200-RPM 2.5″ drives locked in a virtual tie. The Momentus 5400.2 proves significantly faster than the Travelstar 5K100, though.

The Travelstar 7K100 takes the top spot among 2.5″ drives in our compressed file creation multitasking loads. In fact, when coupled with a VirtualDub import, both Travelstars are faster than our desktop Barracuda 7200.9. That scenario proves particularly problematic for our Momentus drives, which are well behind even the 5K100.

Moving to compressed file extraction, the Travelstars continue to fare well. The 7K100 leads our mobile drives, and VirtualDub imports prove especially problematic for the Seagate drives, as they all fall behind the 5K100 yet again.

iPEAK multitasking – con’t

The Seagate drives continue to have problems with multitasking scenarios involving our VirtualDub import, giving the Travelstars plenty of opportunity to strut their stuff. Even in our file copy multitasking scenarios, the 7K100 proves faster than the 7200.1.

The Momentus 7200.1 briefly outpaces the Travelstar 7K100 in our Outlook import multitasking test, but as soon as we fire up a VirtualDub import, the Momentus falls way behind. Hitachi’s caching algorithms and Native Command Queuing implementation are clearly better suited to these tests than Seagate’s.

IOMeter – Transaction rate
IOMeter presents a best-case scenario for command queuing by hammering drives with multiple I/O requests, but it’s not that indicative the kinds of workloads most mobile systems will face. Still, IOMeter gives us another metric to see how these drives compare.

The Momentus 7200.1 leads our mobile drives across all four test patterns, and it’s not that much slower than the Barracuda desktop drive. Curiously, though, the 7K100 is much slower than the other drives, including both 5,400-RPM offerings. Hitachi has been able to replicate these results and says that the lower performance is due to cache optimizations that target workloads more typical of laptop applications. Those cache optimizations apparently aren’t identical to those employed in the 5K100, which is why that drive doesn’t suffer here. In fact, the 5K100 performs reasonably well when compared to the 5400.2, particularly under lighter loads.

IOMeter – Response time

The Momentus 7200.1 has a clear advantage over the other 2.5″ drives when it comes to IOMeter response times. Again, we see the 7K100 way behind the field, although less so with the read-dominated web server test pattern.

IOMeter – CPU utilization

Apart from one isolated spike, CPU utilization is low across the board.

HD Tach
We tested HD Tach with the benchmark’s full variable zone size setting.

The 7,200-RPM Momentus and Travelstar drives trade places at the front of the 2.5″ field in HD Tach’s average read and write speed tests, with Hitachi taking the former and Seagate claiming the latter. In both tests, the Momentus 5400.2 bests the Travelstar 5K100. Keep in mind that sustained read and write speed tests are the best way to highlight our 80GB Travelstar 5K100’s platter capacity disadvantage, though.

Platter capacity should have nothing to do with burst performance, making the 5K100’s poor showing here a little odd. The 7K100’s burst speed isn’t all that impressive, either, with both Seagate drives managing burst speeds that are nearly 20MB/s faster.

Seagate has a slight edge in HD Tach’s random access time test, with both its drives edging out the Travelstars by fractions of a millisecond.

HD Tach’s CPU utilization results are well within the +/- 2% margin for error in this test.

Noise levels
Noise levels were measured with an Extech 407727 Digital Sound Level meter 1″ from the side of the drives at idle and under an HD Tach seek load. Drives were run with the PCB facing up.

Slower spindle speeds prove quieter in our noise level tests, particularly under load. There’s little difference in noise levels between the 5,400-RPM drives, but the Momentus 7200.1 is close to a decibel louder than the Travelstar 7K100 when seeking.

Power consumption
Power consumption was measured for the entire system, sans monitor, at the outlet. We used the same idle and load environments as the noise level tests.

Power consumption results are very close among the 2.5″ drives, with the 5,400-RPM models sipping a little less power at idle and under load. Seagate wins the seek power consumption sweepstakes here, but the Hitachi drives have lower power consumption at idle. Note that our 3.5″ desktop drive consumes nearly 10W more under load than even the most power-hungry mobile drive.

Conclusions
Our test results show very clear performance differences between the 2.5″ mobile Serial ATA hard drives we assembled. At times, those performance differences were surprising, as we certainly didn’t expect to see Seagate’s Momentus 5400.2 beating Hitachi’s Travelstar 7K100 in so many tests. We also didn’t expect the 7K100 to falter so much in IOMeter, or for either Travelstar to perform so strongly in our iPEAK multitasking tests. Those iPEAK results in particular make it clear that the Travelstar drives are capable of spectacular performance. However, whatever caching and command queuing optimizations cause them to do so well in our multitasking tests appear to be hindering performance in other applications.

Although the Momentus drives didn’t fare so well in iPEAK, they did offer better overall performance throughout the rest of our test suite. WorldBench performance was particularly strong, suggesting that the Momentus drives are better suited for the kinds of desktop applications that typically face laptop users. In fact, given the performance we’ve seen today, I’d actually recommend a 5,400-RPM Momentus 5400.2 over a 7,200-RPM Travelstar 7K100 for most users.

Seagate Momentus 7200.1 100GB SATA February 2006

The Momentus recommendation is even easier to make given the fact that Seagate’s five-year warranty gives users an extra two years of coverage compared to Hitachi. You don’t pay much of a premium for the extra coverage, either, as there’s little difference in price between comparable Momentus and Travelstar models. There’s little difference between their noise levels and power consumption, as well, making the Momentus drives an even clearer choice.

Of course, just narrowing our recommendation to Seagate’s Momentus family wouldn’t answer the second question we posed at the start of this comparison: whether there was much of a performance difference between 5,400- and 7,200-RPM notebook drives. Our Momentus test results show that there can be a sizable and consistent gap in performance, and there really isn’t much of a price premium associated with the faster spindle speed. In fact, the Momentus 7200.1 100GB we tested today is actually available for about $15 less than the 5400.2 120GB. Sure you lose out on 20GB of capacity, but the 7200.1 already weighs in at 100GB, and we’d rather have the faster performance.