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300GB SAS Face Off - Hitachi Vs. Seagate
Contributed by Duane Pemberton
Tuesday, 08 January 2008
Last Updated Friday, 25 January 2008
In the IT world of high-speed, redundant data systems, performance is always paramount as is reliability. Companies
don’t want to waste time and money with drives which are sub-standard in either category. Two of the market
leaders right now are Seagate and Hitachi with the largest share of the market belonging to Seagate. Many of you
already know that even before Hitachi acquired IBM’s hard drive division a few years ago, it had been producing
hard drives for the enterprise market for a long time.
Serial Attached SCSI is quickly taking over the entire IT market; replacing the older UltraSCSI 320 as the interface to
have. It supplies more bandwidth with all the benefits of a SCSI interface and uses a much smaller cable. This
technology combines the best of using SCSI commands and the high bandwidth of serial communication. The end result
is the fastest interface currently available.
It’s no wonder why the IT industry is so quickly adopting it in favor of the older SCSI technology and the two
companies represented in this review are primed to help facilitate its needs in the future.
Seagate’s Cheetah line has a legacy of being amongst the fastest available and some of the most reliable. Its 15k
300GB drive is the fastest-spinning, largest capacity unit Seagate currently offers, however, there is a 450GB model
coming out later this quarter.
Four 75 Gigabyte platters are used which means the areal density isn’t near as high as we find on the desktop
markets but the overall rotational speed more than makes up any slack. Sixteen megabytes of cache is mated to the
drive as is the now-typical features such as a fluid bearing motor assembly and a 5-year warranty.
A couple of Seagate exclusives worth pointing out here is its IRAW (Idle Read After Write) which helps keep data safe
thru a verification process during drive idle time. It makes sure that anything sitting in the buffer was properly written.
Secondly is a BMS (Background Media Scan) function which will scan the drive during idle time for potential defects to
help curb any errors before data loss occurs.
Priced from about $500-$600 dollars is about on-par with the enterprise market for a drive of this caliber and there seems
to be ample supply of them in the channel. Costs for these kinds of drives is always higher per capacity than desktop
variants because the majority of R&D from Seagate goes into making them the best performing and longest-lasting
drives possible.
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{mospagebreak_scroll title=Hitachi 15k300}
Power for a full load hovers near 18watts (17.4) which puts it on par with Hitachi, however its idle power drops quite a bit
to 13.2 watts.
Hitachi has been keeping pace with Seagate in the server market and has sold drives under the Hitachi moniker for
years. The Ultrastar 15k300 is a 300GB SAS drive that also spins at 15,000 RPM and has 16MB of cache. Ultrastar used
to exist as an IBM brand and since the acquisition has held on to become Hitachi’s brand as well.
Hitachi uses a fluid dynamic bearing motor which helps reduce noise and drive longevity. Power consumption is also
rather low – coming in at around 18watts under a full load. Beating the Seagate by 1/10 of watt – its idle
power draw is a mere 13.1 watts. A more power efficient drive not only helps lower monthly power bills but also helps to
cut down on heat.
The Ultrastar 15k300’s primary feature over Seagate is its Rotational Vibration Safe-guard (RVS) which the
company claims to help performance in multi-drive systems where vibration is likely to occur. This means if you’re
using a server with these drives, that you should have better reliability with them than the competition.
Its Thermal fly-height control (TFC) means the drive will maintain a consistent fly-height during the reading and writing
process which is said to improve the “soft error rates” and end to end data protection for better data
integrity.
Like Seagate, Hitachi also offers a full 5-year, no-questions-asked warranty – a feature that comes in very handy
to IT managers who want a no-hassle, long-term replacement guarantee.
{mospagebreak_scroll title=Benchmarks}
Benchmark Setup:
XFX 680iLT SLI Motherboard
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MSI P35 Platinum Motherboard
Intel Core2Duo X6800 "Xtreme" 2.93GHz
2GB OCZ PC2-8000 DDR2 DRAM
Seagate 400GB SATA Drive
Sony DVD-ROM Drive
Windows Vista Ultimate
Antec Quattro 850w PSU
LSI Logic MegaRAID SAS 8708ELP PCI-E Controller
We used a pair of each drive Drives in all of testing of RAID 0
Software Used: PCMark 2005 and HDTach
{mospagebreak_scroll title=Conclusion and Ratings}
With regards overall performance, Seagate is clearly taking the lead here under our somewhat limited testing.
Unfortunately we didn’t have enough of each drive to test RAID 5 and RAID 10 – that said, the Hitachi
Ultrastar still provides excellent performance and had we had other RAID modes to test under – who knows what
the turnout could’ve been like.
Both units represent the latest performance in the SAS market sector and are available at most leading PC hardware
suppliers. Power use is so close we’ll have to call it a draw, however, the end performance win here tips our hat to
Seagate. Hitachi, on the other hand seems as if it’s built to take more abuse with its vibration protection so if your
environment of use for it is riddled with vibration go for the Hitachi.
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In the end, however, most folks will use these drives in a server farm inside some environmentally stable room
somewhere and that’s where the Seagate Cheetah 15k.5 drive will server you with the utmost in performance and
the legendary Seagate reliability.
Ratings:
Seagate 15k.5 300GB - 9/10
Hitachi Ultrastar 15k300 - 8/10
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