by Aleksey Meyev
03/06/2008 | 10:57 AM
Some time ago we tested 2.5-inch hard disk drives with a storage capacity of 250 gigabytes, and now we want to check out external storage devices based on them. There have also appeared external HDDs with a capacity of 300 gigabytes but their spindle rotation speed is lower at 4200rpm.
Who may need such a HDD? People who have to carry large amounts of data from one computer to another, of course! First of all, it is people who are into image and video processing. High-definition video that has become popular nowadays comes in very heavy files weighing tens of gigabytes. External HDDs of the maximum storage capacity may also be appealing for a user who carries not only data but also applications with him. There are now a wide range of programs, from office suites to games, which can be started up right from an external storage device without installation. And of course, there is a category of users who just want to have the fastest and highest-capacity computer-related products available. And few of them are willing to put up with the drawbacks of external HDDs based on 3.5-inch disks which are too large and heavy.
We have two external drives from Fujitsu’s HandyDrive series. We tested one model from this series in our review of 160GB external HDDs, and now it’s time to check out the models with higher storage capacity. Every model in this series looks like the rest but differs with the model number and capacity marked on the case (the hard disk inside is different too, of course). The glossy black case looks pretty but gets dirty and scratched easily. This HDD may lose its pretty looks soon enough unless you care about it. The included pouch will help you in that.
The drive’s mini-USB and power connectors (you may need the latter if the computer cannot provide enough power over the USB) are sealed with special caps. There is no power adapter in the kit. Instead, you get a second cord for powering the HDD by a second USB port. We didn’t use the second cord during our tests, though. The kit includes the required minimum of accessories: a user manual, USB cable, and a CD with an electronic version of the user manual.
These external HDDs proved to be rather secretive. They reported their own model names rather than the models of the hard disks installed in them. Moreover, the 250GB model was identified like the 300GB one, namely MME2300UB. There are no special secrets about the 300GB drive, though. It obviously comes with Fujitsu’s MHX2 BT series disk that has three platters and a spindle rotation speed of 4200rpm. Fujitsu just doesn’t have other models of hard disks with that storage capacity. The 250GB model is more of a mystery. We guess it uses either a junior model from the MHX2 BT series or a senior model from the MHY2 BH series (two platters and a spindle rotation speed of 5400rpm). We’ll check this out in our tests.
These two HDDs are especially interesting as they offer an eSATA interface besides the traditional USB. The eSATA interface cannot provide power to the external HDD, so there are two variants of powering the latter. You can use an external power adapter, which is problematic because no adapter is included into the kit whereas the eSATA connector has nonstandard polarity (the “minus” corresponds to the central pin and the “plus” to the outer pin rather than vice versa). Or you can connect the drive via both USB and eSATA. In this case the HDD is powered by the USB and transfers data via eSATA.
The HDDs are nothing special on the outside: a typical black “cigarette-case” with two interface connectors, a power connector (for the missing adapter) and a button all in one butt-end. Having installed the included software on your PC, you can press the button to back up your data to the external HDD according to the specified settings. That’s a nice addition to the drive’s functionality, but the button might have been bigger rather than just a section of the metallic panel that you can press.
A neat pouch for carrying the drive is included into the kit but no eSATA cable could be found.
When connected to a PC, the 250GB and 300GB models were identified as Fujitsu K2200T762 and Fujitsu K201T782 respectively. It’s clear about the second model – it obviously comes with a MHX2300BT hard disk. As for the 250GB model, we have to wait for the tests to show us, just like with the above-described HDD from Fujitsu of the same capacity.
Running a little ahead, we can tell you that we tested the 300GB model using both of its interfaces and the 250GB model with the eSATA interface only.
Toshiba’s 160GB model used to differ from other external drives with an unusual white LED, but the 250GB model uses a blue LED. So, this HDD is just a typical gray case with mini-USB and power connectors. The accessories are frugal: a USB cable that can connect to a second USB port for power supply (by the way, this is the only drive that proved to need this additional power), user manual, and a disc with an electronic version of the manual.
This HDD was honest about its interior, introducing itself as a Fujitsu MHY2250BH.
At the time of our tests the Transcend TS250GSJ25S was the highest-capacity model in the StoreJet series. This drive has a typical exterior design, differing from other external HDDs with the shape and color. It offers a USB interface and a power connector.
Included into the kit are a user manual, CD, and a USB cable (with additional power supply from a second USB port). A Samsung HM250JI disk is installed inside this external storage.
The last product included into this review is a no-name 250GB external HDD. It has a typical exterior design and a minimum of connectors. It offers a USB port (a full-size connector rather than mini-USB) and no power connector. Its accessories include a USB cable (it can provide additional power from a second USB port) and a pouch. This HDD is based on a Fujitsu MHY2250BH hard disk.
The following testing utilities were used:
Testbed configuration:
We installed the generic OS drivers for the drives and formatted them in FAT32 and NTFS as one partition with the default cluster size. For some tests 32GB partitions were created on the drives and formatted in FAT32 and NTFS with the default cluster size, too. The eSATA interface was provided by a Promise SATA300 TX4302 controller.
IOMeter is sending a stream of read and write requests with a request queue depth of 4. The size of the requested data block is changed each minute, so that we could see the dependence of the drive’s sequential read/write speed on the size of the data block. This test is indicative of the highest speed the drive can achieve.
The eSATA interface is just incomparable to the USB in processing small data blocks as well as in terms of maximum speed. Perhaps the eSATA controller with its caching algorithms contributes to the high speed with small data chunks. But when it comes to large data blocks, it is purely a battle of interfaces and eSATA wins it easily.
Comparing the USB-connected drives, they are only different in terms of maximum speed. The Transcend is the only one to reach a speed of 30MBps. The Toshiba and the USB-connected 300GB Teac are slow. But the latter delivers superb performance when connected via eSATA.
The HDDs from Teac are beyond competition at writing when connected via eSATA. Take note that the 300GB model is ahead of its 250GB mate by 3MBps at both writing and reading. This difference is due to the speed characteristics of the employed hard disks.
The USB-connected HDDs split up. The two models from Fujitsu show the highest speed but don’t reach 30MBps. The no-name HDD is almost as fast as the leaders but slows down on 64KB data chunks. The Transcend has a lower maximum speed. The USB-connected Teac behaves alike to the Transcend but has problems processing 128KB data blocks. The Toshiba is the worst drive in this test. It achieves its maximum speed on very large data blocks only and is slower than the other HDDs on small ones.
In this test IOMeter is sending a stream of requests to read and write 512-byte data blocks with a request queue of 1 for 10 minutes. The total number of requests processed by the HDD is over 60 thousand, so we get a sustained response time that doesn’t depend on the HDD’s buffer size. The results are sorted by read response time.
The HDDs are ranked according to the spindle rotation speed of their disks. The Teac is somewhat worse than the other 250GB models at both reading and writing. It is obviously based on a Fujitsu MHX2 BT series drive that has a spindle rotation speed of 4200rpm as opposed to 5400rpm of the other 250GB models. Judging by the characteristic response time, the 250GB HandyDrive from Fujitsu is based on a 5400rpm MHY2 BH series disk, too. The somewhat higher response time of the Transcend HDD at writing can be explained easily. It is based on a Samsung disk, and Samsung’s HDDs have low efficiency of deferred writing.
Interestingly, it is the no-name HDD that wins this test, even though by a very small margin.
In the Database pattern the drive is processing a stream of requests to read and write 8KB random-address data blocks. The ratio of read to write requests is changing from 0% to 100% throughout the test while the request queue depth varies from 1 to 256.
Few people would install high-speed databases on external media whose speed is of course low. That’s why we won’t analyze the results deeply. We’ll just show you a table with the results and focus on the most interesting facts using diagrams.
We will show you three diagrams as the most illustrative ones. One diagram is for the Transcend drive which is the only one based on a Samsung hard disk (to remind you, the rest of the external HDDs are based on Fujitsu’s hard disks). The second diagram is for the 300GB Teac connected via USB. This drive shows the typical behavior of most of the reviewed HDDs. The third diagram shows the same Teac but connected via eSATA. You can use the links below to see the other diagrams.
Comparing the first two diagrams you can see that this test depends on the hard disk installed within the external storage. Compared with the Fujitsu-based drive from Teac, the Samsung-based Transcend features higher scalability of performance depending on the request queue depth as well as a better behavior under the most difficult load when the amount of reads and writes is about the same. The Transcend is worse in terms of deferred writing efficiency, though.
You can also compare the performance of the Teac with the different interfaces. When connected via eSATA, this HDD is slower at long queue depths when there is a high percentage of writes, but more efficient at processing read requests. The fact is the eSATA interface, as opposed to the USB, supports requests reordering according to NCQ technology. It is this technology that ensures such a substantial growth of the graphs in the left part of the diagram when we switch from USB to eSATA.
This group of tests simulates disk loads typical of servers and workstations. Like the Database pattern, these loads are not relevant for mobile HDDs, so these results are of theoretical interest rather. The names of the patterns are self-explanatory. The Workstation pattern is used with the full capacity of the drive as well as with a 32GB partition. The request queue is limited to 32 requests in the Workstation pattern.
The results are presented as performance ratings which are calculated by the following formulas:
Rating (File-Server) = Total I/O (queue=1)/1 + Total I/O (queue=4)/2 + Total I/O (queue=16)/4 + Total I/O (queue=64)/6 + Total I/O (queue=256)/8,
Rating (Web-Server) = Total I/O (queue=1)/1 + Total I/O (queue=4)/1 + Total I/O (queue=16)/2 + Total I/O (queue=64)/4 + Total I/O (queue=256)/6,
Rating (Workstation) = Total I/O (queue=1)/1 + Total I/O (queue=2)/1 + Total I/O (queue=4)/2 + Total I/O (queue=8)/3 + Total I/O (queue=16)/4.
The Samsung-based drive from Transcend wins this test, but the gap from the other 250GB models is very small. The difference between the installed hard disks doesn’t show up here. Interestingly, the Teac drives are slower than the leaders, their eSATA interface being of no help in this test. The high response time of the 4200rpm HDDs affects their results. The HDDs with a storage capacity of 300 gigabytes and USB interface, i.e. the Fujitsu HandyDrive 300GB and the USB-connected Teac HD-15-OTC 300GB, are the worst in this pattern.
This test contains write requests, and the Transcend gives way to the 250GB models based on Fujitsu’s disks. It is followed by the eSATA-connected Teac drives whereas the Fujitsu HandyDrive 300GB and the USB-connected Teac HD-15-OTC 300GB are losers again.
There are two groups with similar results: the USB-connected 250GB models are in the lead, the Transcend being somewhat faster than the others. And the 300GB models together with the eSATA-connected TEAC-HD-15C-OTC are in the slower group.
The standings do not change when we limit the test zone to 32 gigabytes.
The multi-threaded tests simulate a situation when there are one to four clients accessing the hard disk at the same time. The depth of the outgoing request queue is varied from 1 to 8.
We’ll discuss diagrams for a request queue of 1 as the most illustrative ones. When the queue is longer, the speeds depend but little on the number of applications.
The eSATA-connected Teac is unrivalled when reading one thread. It is followed by the Transcend. Next go the other 250GB models with USB interface whereas the 300GB models with USB interface are the slowest again. Interestingly, the eSATA-connected 300GB Teac is considerably faster than its 250GB counterpart.
The eSATA interface loses its advantage at two read threads. The 300GB model is still in the lead, but the gap is small. The 250GB model sinks suddenly to last place.
When the number of threads is increased further, the eSATA-connected drives from Teac restore their leading positions. The 250GB model doesn’t show a performance hit whereas the 300GB model slows down less than the USB-connected models do. You can see the Transcend being the worst drive at three threads but faster than the USB-connected 300GB models at four threads.
The eSATA-connected drives from Teac are in the lead when writing one thread. They enjoy a 10MBps lead over the closest pursuer. The Transcend is the slowest drive here but it is not far worse than the other USB-connected models. You can see the USB-connected 300GB drives are as fast as the 250GB models in this test.
When the number of write threads is increased to two, the USB-connected models remain unaffected whereas the eSATA-connected drives from Teac lose some speed, but still stay on top places.
The standings do not change much when there are even more write threads to be processed. You can only note the Transcend speeding up suddenly at four threads and rising from last place to the middle of the group of the USB-connected drives.
First, you can have a look at the data-transfer diagrams of the drives:
|
|
|
|
|
|
|
|
We will compare the drives according to the read speed at the beginning and end of the disk:
The 250GB Teac is as fast as the 300GB models, so it is indeed based on a 4200rpm Fujitsu MHX2BT disk.
Note that the USB limits the speed of the 5400rpm HDDs both at the beginning and end of the partition where the speed is the highest and lowest, respectively. So, the interface is the main performance-affecting factor of mobile HDDs. 4200rpm HDDs with eSATA interface are considerably faster than 5400rpm HDDs with USB interface.
Now let’s compare the results of the WinBench 99 tests performed on a 32GB partition.
The results are most illustrative: the USB-connected models have similar results, the 250GB HDDs being barely faster than the 300GB ones notwithstanding the higher spindle rotation speed. The Teac drives with eSATA interface and slow disks inside are considerably faster, especially in terms of Business Disk WinMark 99.
When the partition is formatted in NTFS, the USB interface is somewhat closer to eSATA in High-End Disk WinMark 99 but still slower than it in the Business subtest.
Now we will check performance of the hard disk drives with the FC-Test program. Two 32GB partitions are created on the drives and formatted in NTFS and then in FAT32. After that a file-set is created of the hard disk. It is then read from the disk, copied within the same partition and then copied into another partition. The time taken to perform these operations is measured and the speed of the drive is calculated.
To remind you, the Windows and Programs file-sets consist of a large number of small files whereas the other three patterns (ISO, MP3, and Install) include a few large files each.
This test produces too much data, so I will only discuss the results of the MP3, ISO and Install patterns which illustrate the most characteristic use of external HDDs. You can find the diagrams for the remaining two patterns by following the links below.
Results of the Windows and Programs patterns
There are no surprises at writing: the eSATA-connected Teac are in the lead. Next go the 250GB models with USB interface. The Fujitsu HandyDrive 300GB and the USB-connected Teac HD-15-OTC 300GB are losers. These two models are based on big, but slow disks.
Results of the Windows and Programs patterns
The eSATA-connected drives enjoy a larger advantage when reading. The 300GB models with USB interface are traditionally slow, but the gap is about 2MBps or less than 10%. This is not a big tradeoff for the extra 50 gigabytes of storage space.
Results of the Windows and Programs patterns
The firmware algorithms of the particular hard disk affect the speed of copying. It is thanks to them that the Transcend goes ahead (to remind you, this external storage is based on a Samsung hard disk whereas the others are based on Fujitsu disks) and is almost as fast as the eSATA-connected HDDs.
Results of the Windows and Programs patterns
The standings do not change much when the drives are copying files from one partition to another. The eSATA-connected Teac are in the lead, followed by the Transcend. The others have considerably lower speeds.
Results of the Windows and Programs patterns
The overall picture hasn’t changed. Note that the eSATA interface has the smallest advantage at writing. It is because the speed of the HDDs is close to the peak bandwidth of the USB here but exceeds it at reading.
The 300GB Teac with eSATA interface proves to be somewhat faster than its 250GB mate once again.
Results of the Windows and Programs patterns
The eSATA interface triumphs again.
Results of the Windows and Programs patterns
Results of the Windows and Programs patterns
The copying tests produce the same picture as in FAT32. The eSATA-connected HDDs go first, closely followed by the Transcend. The others are slower. Take note that the Samsung-based drive from Transcend has a larger advantage over the same-class models when copying larger files.
Now it’s time to sum up the results. There were no surprises, actually. Modern external hard disk drives are limited by the bandwidth of the USB interface. It is only with a faster interface, e.g. with eSATA, that you can reveal the full potential of a 2.5-inch hard disk drive. Therefore the leaders of this test session are the drives from Teac. Thanks to eSATA they were faster than their USB-connected opponents even though they are based on 4200rpm rather than 5400 hard disks as the rest of the tested external HDDs. There is only one inconvenience about the current implementation of eSATA. This interface doesn’t provide power to the external device via the interface cable. You have to power the drive up by an external power adapter or, rather absurdly, by a USB cable. Hopefully, the next update of the eSATA standard will solve this problem.
If you want to use a USB drive for some reason, there is no difference in speed between them. Your choice should be based on such subjective characteristics and exterior design and ergonomics. The Fujitsu HandyDrive 300GB was somewhat slower than the others due to its 4200rpm hard disk, though. It’s up to you to decide if the extra 50 gigabytes of storage space make up for the 10% reduction in speed. Generally speaking, external HDDs with USB interface have stopped to progress. Although the capacity and speed of hard disk drives proper has been growing up, the interface bandwidth is still about 30MBps.
We’d like to specifically note the high performance of the Transcend drive at copying which is due to the Samsung disk it has inside.
