2 TB duel: Seagate Barracuda LP vs Western Caviar Green - BeHardware
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Written by Marc Prieur

Published on July 29, 2009

URL: http://www.behardware.com/art/lire/764/

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Hitachi were the first to launch a hard drive with a 1 TB capacity back at the beginning of 2007: the 7K1000. At the time, this drive used five 200 GB platters, the whole drive running at 7200 rpm. Since then, perpendicular writing technology has made so much progress that both Western and Seagate have launched 2 TB drives!

To reach such a capacity, both manufacturers have gone for a 4 platter architecture, each platter at 500 GB. Western were the first to announce such a drive, the Caviar Green WD20EADS. Launched in january 2009, it has long held the uncontested record in its category. This didn’t take into account the new range launched by Seagate in April, the Barracuda LP, which had the same capacity.

5900 rpm vs IntelliPower
Whether they be stamped Western or Seagate, 2 TB drives use lower rotation speeds than the standard 7200 rpm. Western was the first to relaunch lower speeds in its Green range, followed by Samsung – who have limited themselves to 1.5 TB for the moment – and now Seagate.

The only problem is that Western is still not communicating on the rotation speed of its platters: although we understood the rationale behind this policy at first, now that other manufacturers have followed suit, why keep it a secret? We now only know that the Caviar Greens have IntelliPower technology, which is, I quote, “An excellent compromise between rotation speed, transfer speed and cache size resulting in significant energy savings and exceptional performance.” In practice, rotation speed is around 5400 tpm.

In contrast Seagate has no qualms about revealing the rotation speed of its Barracuda LPs: 5900 rpm. This rotation speed is unusual compared to what we’re used to: 5400 rpm and 7200 rpm. But why not?
Perfect for some uses
5400/5900 rpm drives are a good choice for several types of usage. The first, of course is for a machine that doesn’t need the highest performance but a significant storage capacity and good environmental spec, such as a PC Home Cinema. But they will also serve well in an NAS.

They also have their place within a high-performance PC, as a secondary storage facility. You could for example use a VelociRaptor, or even an SSD, for your everyday applications and a 5400 rpm for your data: your holiday Blu-ray and the 100 daily photos of your youngest can easily be stored here!

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The test

The test
For this test, we used two 2 TB hard drives and for comparison purposes included two best-sellers from the 1 TB ranges:

- WD Caviar Green WD20EADS (5400 rpm, 32 MB of cache)
- Seagate Barracuda LP ST32000542AS (5400 rpm, 32 MB of cache)
- Samsung SpinPoint F1 HD103UJ (7200 rpm, 32 MB of cache)
- WD Caviar Green WD10EADS (5400 rpm, 32 MB of cache)

Note that both the WD20EADS and the ST32000542AS have acoustic management support in theory, but in practice we didn’t manage to get it working: access times remained the same in spite of modification of settings.
The test protocol
Various readings were taken in the course of this comparison. First of all we were interested in the “synthetic” performances of these drives: cache and sequential speeds and average acces time. Next, were more practical tests, first of all involving an applicative performance index based on PC Mark Vantage and then a server load type simulation of files with IOMeter. This was followed by an evaluation of writing and reading of various groups of files.

These files were made up of the following:

- Large: 6 files (on average 2.2 GB) totalling 13.2 GB
- Medim sized: 7.96 GB of 10,480 files (each averaging 796 KB)
- Small sized: 2.86 GB of 68,184 files (each averaging 44 KB)

The source or target of reading or writing on the drive was a RAID of two Raptor 150 GB drives so as to make sure we weren't limited. This type of measurement is worthwhile because, while the sequential speed gives us an idea of the performance in copying large files, things can be different with smaller ones.

All measurements were taken without noise level reduction but we did also carry out some measurements afterwards with this option activated. The test machine was based on an X38 chipset mounted on an ASUSTeK P5E motherboard while Serial ATA ports were configured in the bios in AHCI (Advanced Host Controller Interface) so that NCQ could be used.

In addition to performance we also measured temperature after 2 hours of intensive use, as well as energy consumption. Noise pollution of each drive was also evaluated.

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Synthetic measurements

Synthetic measurements

Measured with h2benchw, the cache speed was faster on the Western than the Seagate. There is no improvement from one Western generation to the next.

With a rotation speed of 5900 rpm, the Barracuda LP has a "natural" advantage of around 0.5 ms in terms of access times. In practice however Seagate has succeeded in doing much better and at 12.6 ms the Barracuda LP is even faster than a SpinPoint F1 at 7200 rpm. In spite of taking the reading several times, the result remained constant. With the Westerns, access times are almost the same on both generations of drive.

We now move on to sequential read and write speeds, still using h2benchw to take our readings. This time there’s an improvement of around 17% in speeds, the surface density differing between the WD10EADS (333 GB / platter) and the WD20EADS (500 GB / platter). The performance advantage remains with Seagate, to the order of between 13% and 15% while the difference in speed of rotation is lower than 10%.

These graphs illustrate the different speeds according to how close to the centre of the drive you are. There isn’t a notable difference between the drives, speeds gradually falling off.

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PC Mark Vantage

PC Mark Vantage
We now move on to less synthetic tests, starting with an index of hard drive performances in PC Mark Vantage. FutureMark reproduces a set of reading/writing tasks on the drive, namely a Vista start-up, loading of applications (Word, Photoshop, IE, Outlook), the manipulation of multimedia files (photo, video, music), games (loading of Alan Wake) and disk scan with Windows Defender.

The impressive performances of the Barracuda LP in synthetic tests are not repeated here and it is quite close to the 2 TB Caviar Green. There is no significant increase in performance in this test as a result of the new densities and the scores are down on the 7200 rpm stock drive, the SpinPoint F1 and far behind the VelociRaptor. If you want very good responsiveness for your OS and applications, you’ll need to install them elsewhere than on such a drive, ideally of course on an SSD.

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Management of files

File copying
This brings us to file copying. We measure reading and writing of diverse groups of files. These groups were composed of:

- A collection of large files: 6 files (on average 2.2 GB) totalling 13.2 GB
- Medim sized: 7.96 GB of 10,480 files (each averaging 796 KB)
- Small sized: 2.86 GB of 68184 files (44 KB on average)

The source or target of reading or writing on the drive was a RAID of two Raptor 150 GB drives.

Whether reading or writing, the 2 TB drives do pretty well and are never far off the pace set by the SpinPoint F1 or the VelociRaptor. In some cases they even outdo them!

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I/O Meter

IOMeter is used to simulate the load in a multi-user environment by using a server type file load comprised of 80% reading and 20% writing all in a 100% random manner on the drive. In this type of situation, NCQ can be particularly useful because of multiple concurrent commands. In this test, we measured performances expressed in inputs/outputs per second (IO/s) with 1, 2, 4, 8, 16, 32, 64 and 128 simultaneous commands.

To give a clearer vision of the results we removed the performances of the VelociRaptor from the graph: for info it obtained 150 I/Os per second with 1 command and 356 with 128. Strangely, and we have no explanation for this, the WD20EADS’s performance is quite a bit down on the WD10EADS here (no synthetic element gives a clue here).

Management of NCQ remains effective however, so much so that at 32 commands and more the WD20EADS is up on the the SpinPoint F1, that is however at 7200 rpm. Although the Barracuda LP gives comparable performance with 1 to 2 simultaneous commands, it seems to suffer from inefficient reorganisation of commands with 4, 8 and 16 commands, before improving again.

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Energy consumption, noise, temperature

Energy consumption
Here is the data for energy consumption for each of the drives that we were able to read with a clip-on ammeter, by reading voltages used on the 5V and 12V lines.

In its 2 TB version, the Caviar Green is much more demanding in terms of rotation than the 1 TB, but the same for access. The Barracuda LP is a little more economical when it comes to rotation but consumes much more during access.
We then meausred the temperature of the drive after 2 hours of intensive use in IOMeter. These measurements were taken with the HDD outside of the casing, without the fan, each of the drives slightly raised. The temperature was measured in two places using an infrared thermometrer, above the middle of the drive and at the hottest point on the left side. We also read the temperature on the internal drive sensor (SMART). As usual the SMART sensor on the SpinPoint F1 under-evaluated the temperatures, something we already know from our previous tests on this model.

In spite of using 4 instead of 3 platters, the 2 TB Caviar Green is only 1°C warmer than the 1 TB version. The Barracude LP is 2 to 3°C hotter and has comparable values to a 3 platter 7200 rpm drive such as the SpinPoint F1.
To take this we placed each drive so as to avoid all vibrations (seeing as they were placed on the desk). A sonometer was placed 10 cm above the drive so as to measure noise pollution, the PC used being without any fan so as to isolate the sound of the drive.

The 2 TB Caviar is very quiet in spite of record capacity, with comparable levels to the previous 1 TB version. In contast the Barracuda LP is disappointing with noise levels closer to a 7200 rpm drive than a 5400 rpm.

To give an idea of the levels of noise produced by these drives we wanted to record them as we usually do. Unfortunately, our recording methods are not sensitive enough to pick up the low sound levels of the 5400 rpms and we couldn’t record the levels during rotation.

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Although magnetic hard drives are no competition for SSDs in performance terms, they still have the highest capacities. It is now possible to buy 2 TB of storage space for under €250; about the price of an entry level SSD that is 16 times as small! Of course the two technologies are more a complement to each other than in direct competition and many users will now choose an SSD for the main drive and a hard drive for storing media.

After this review of two of the 2 TB drives currently available, the Western Digital comes out on top. Sure, with 5900 rpm, the Barracuda LP does give faster performances at times, but this is not systematic, especially with better NCQ management from Western Digital, and the drive temperature and noise levels are significantly higher than those on the WD model. The Barracuda LP is almost as noisy and loud as the Samsung SpinPoint F1, which only has 3 platters and turns at 7200 rpm! In contrast the WD20EADS is comparable to the 1 TB WD10EADS and remains very quiet and heats up a lot less. The Western is also coming in at around €214 (average of 5 most expensive) compared to €258 for the Seagate. We therefore strongly recommend the WD20EADS.

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