Great Maximum Recover Data Hard Drive Laptop

Faceoff at One Terabyte: Seagate's Barracuda ES.2 and WD's Caviar GreenPower

2009-07-29T21:16:00.000-07:00

Multi-User Performance

Unlike single-user machines (whether a desktop or workstation), servers undergo highly random, non-localized access. StorageReview simulates these multi-user loads using IOMeter. The IOMeter File Server pattern balances a majority of reads and minority of writes spanning requests of varying sizes.

IOMeter also facilitates user-configurable load levels by maintaining queue levels (outstanding I/Os) of a specified depth. Our tests start with the File Server pattern with a depth of 1 and double continuously until depth reaches 128 outstanding I/Os.

Drives with any sort of command queuing abilities will always be tested with such features enabled. Unlike single-user patterns, multi-user loads always benefit when requests are reordered for more efficient retrieval.

For more information click here.

The Barracuda ES.2 delivers substantial improvement over the ES 750 when it comes to our multi-user test. While both drives commence with nearly identical results under a linear load, the ES.2 scales significantly better under concurrency to top the chart when it comes to 7200 RPM units. The ES.2's improvements approach a commendable 40% over the relatively modest ES 750.

The Caviar GP unsurprisingly lags its performance-oriented predecessor by margins of approximately 10%. The gap closes as queue depths hit extremely heavy levels, however.

Source: http://www.storagereview.com/1000.sr?page=0%2C5

Faceoff at One Terabyte: Seagate's Barracuda ES.2 and WD's Caviar GreenPower

2009-07-29T21:14:00.000-07:00

Gaming Performance

Three decidedly different entertainment titles cover gaming performance in StorageReview's test suite.

FarCry, a first-person shooter, remains infamous for its lengthy map loads when switching levels.

The Sims 2, though often referred to as a "people simulator," is in its heart a strategy game and spends considerable time accessing the disk when loading houses and lots.

Finally, World of Warcraft represents the testbed's role-playing entry; it issues disk accesses when switching continents/dungeons as well as when loading new textures into RAM on the fly.

For more information, please click here.

The Barracuda ES.2 builds upon the ES 750 with a modest but measurable 6% gain in our replay of FarCry's disc access. The Caviar GP, on the other hand, trails the WD7500AAKS by 11%.

The Sims 2 places the GP about 15% behind the WD7500AAKS. Seagate's latest also slips slightly, lagging its forerunner by about 2%.

It is World of Warcraft that places the biggest gap between WD's two drives. The GP lags the WD7500AAKS by 18% here. Meanwhile, the Barracuda ES.2 regains some form and manages a 13% lead over the ES 750.

Source: http://www.storagereview.com/1000.sr?page=0%2C4

Faceoff at One Terabyte: Seagate's Barracuda ES.2 and WD's Caviar GreenPower

2009-07-29T21:11:00.000-07:00

Single-User Performance

StorageReview uses the following tests to assess non-server use:

StorageReview.com Office DriveMark 2006- A capture of VeriTest's Business Winstone 2004 suite. Applications include Microsoft's Office XP (Word, Excel, Access, Outlook, and Project), Internet Explorer 6.0, Symantec Antivirus 2002 and Winzip 9.0 executed in a lightly-multitasked manner.

StorageReview.com High-End DriveMark 2006- A capture of VeriTest's Multimedia Content Creation Winstone 2004 suite. Applications include Adobe Photoshop v7.01, Adobe Premiere v6.5, Macromedia Director MX v9.0, Macromedia Dreamweaver MX v6.1, Microsoft Windows Media Encoder 9.0, Newtek Lightwave 3D 7.5b, and Steinberg Wavelab 4.0f run in a lightly-multitasked manner.

For more information, please click here.

WD's Caviar GP turns in a StorageReview Office DriveMark of 794 I/Os per second (IOps), lagging its predecessor by about 10%.

The Seagate Barracuda ES.2's showing of 588 IOps builds very incrementally on the score achieved by the ES 750, an almost negligible 2% increase.

In our higher-level, content-creation-oriented High-End DriveMark, both newcomers stumble a bit when compared to previous models. The WD10EACS lags the older WD7500AAKS by almost 13%. Perhaps more surprisingly, however, the Barracuda ES.2 regresses when contrasted with the ES 750, trailing its predecessor by 15%.

Source: http://www.storagereview.com/1000.sr?page=0%2C3

Faceoff at One Terabyte: Seagate's Barracuda ES.2 and WD's Caviar GreenPower

2009-07-29T21:08:00.000-07:00

Access Time and Transfer Rate

For diagnostic purposes only, StorageReview measures the following low-level parameters:

Average Read Access Time- An average of 25,000 random read accesses of a single sector each conducted through IPEAK SPT's AnalyzeDisk suite. The high sample size permits a much more accurate reading than most typical benchmarks deliver and provides an excellent figure with which one may contrast the claimed access time (claimed seek time + the drive spindle speed's average rotational latency) provided by manufacturers.

Average Write Access Time- An average of 25,000 random write accesses of a single sector each conducted through IPEAK SPT's AnalyzeDisk suite. The high sample size permits a much more accurate reading than most typical benchmarks deliver. Due to differences in read and write head technology, seeks involving writes generally take more time than read accesses.

WB99 Disk/Read Transfer Rate - Begin- The sequential transfer rate attained by the outermost zones in the hard disk. The figure typically represents the highest sustained transfer rate a drive delivers.

WB99 Disk/Read Transfer Rate - End- The sequential transfer rate attained by the innermost zones in the hard disk. The figure typically represents the lowest sustained transfer rate a drive delivers.

For more information, please click here.

The Barracuda ES.2 weighs in with a 12.7 millisecond (ms) seek time, about a half-millisecond above the drive's predecessor. Accounting for the drive's 7200 RPM spindle speed (4.2 ms latency) leaves the unit with a measured access time of 8.5 ms... bravo Seagate, right on the money. The ES.2 joins the ES 750 now as the second consecutive Seagate offering that meets the firm's claimed specs... a welcome turnaround from a company that used to publish overly optimistic claims that often were missed by its ATA/SATA drives.

We have to take a different approach when assessing the Caviar GP's seek time since WD does not explicitly give users the drive's spindle speed. The GP turns in a measured access time of 15.0 ms, a score that lags the 7200-RPM WD7500AAKS by a significant margin. The WD7500AAKS's measured seek time when accounting for 4.2 ms of 7200 RPM latency is 9.5 ms (missing the firm's claim by over half a millisecond). Assuming the GP also shares such a seek time, that leaves us with 15 ms [measured access time] minus 9.5 ms [assumed seek time] which equals 5.5 ms, almost exactly the rotational latency associated with a 5400 RPM spindle speed.

Seagate's latest is the first SATA drive to bust through the 100 MB/sec plateau through achieving 104 MB/sec of transfer in its outermost zones. Rates decay down to a more pedestrian 53.3 MB/sec.

The Caviar GP's outer-zone score clocks in at 79.8 MB/sec and as a result lags the older, less dense WD7500AAKS by 21%. Assuming similar sector-per-track zone configurations, a 7200 RPM drive would boast a 33% advantage over a 5400 RPM unit. The difference between the GP and the WD7500AAKS is less than that, likely of course due to a density advantage on the GP's part. Nevertheless, this second low-level diagnostic again suggests a 5400 RPM spindle speed.

First half of the Barracuda ES.2's Transfer Rate Graph

Second half of the Barracuda ES.2's Transfer Rate Graph

First half of the Caviar GP's Transfer Rate Graph

Second half of the Caviar GP's Transfer Rate Graph

Some Perspective

It is important to remember that seek time and transfer rate measurements are mostly diagnostic in nature and not really measurements of "performance" per se. Assessing these two specs is quite similar to running a processor "benchmark" that confirms "yes, this processor really runs at 2.4 GHz and really does feature a 400 MHz FSB." Many additional factors combine to yield aggregate high-level hard disk performance above and beyond these two easily measured yet largely irrelevant metrics. In the end, drives, like all other PC components, should be evaluated via application-level performance. Over the next few pages, this is exactly what we will do. Read on!

Source: http://www.storagereview.com/1000.sr?page=0%2C2

Faceoff at One Terabyte: Seagate's Barracuda ES.2 and WD's Caviar GreenPower

2009-07-29T21:05:00.000-07:00

Western Digital Caviar GP

Model Number

Capacity

WD5000AACS

500 GB

WD7500AACS

750 GB

WD10EACS

1000 GB

Lowest Real-Time Price (1000 GB):

$107.49

WD's offering in the terabyte sweeps is the WD10EACS, or the Caviar "GreenPower" (GP). Like Seagate, WD takes advantage of additional development time to offer a one-terabyte capacity incorporating four 250-gigabyte platters seek time and equips the GP with a standard 16-megabyte buffer. A three-year warranty backs the drive.

rather than the five 200-gigabyte discs found in the Hitachi Deskstar 7K1000. The firm claims an 8.9 millisecond

The focus, as one can guess from the drive's name, is squarely on environmental concerns. WD, more so than Seagate, banks on power consumption issues becoming more and more a significant part of overall drive ownership and operation concerns as time passes. Through an aggressive deployment of a variety of features, the GP line boasts of power dissipation of up to 40% less than baseline standards, a figure that WD claims will save up to $10 per year per drive when considered under 24x7 operation.

The manufacturer is careful in not directly citing spindle speed, instead nominally positioning the Caviar GP as a "7200 RPM-class" drive. Under its "IntelliPower" moniker, WD claims a "A fine-tuned balance of spin speed, transfer rate and cache size designed to deliver both significant power savings and solid performance." Some folks have misinterpreted some admittedly vague specs on WD's website. Under "Rotational Speed," the manufacturer cites "IntelliPower (5400 to 7200 RPM)." This does not mean the drive dynamically changes its spindle speed during operation... indeed, such a feature would entail considerable mechanical engineering and would in many ways defeat the point -- rapidly accelerating and decelerating the spindle's speed would increase rather than decrease net power draw. Rather, the IntelliPower term indicates that the GP family as a whole does not have a set spindle speed (nor a set buffer size, for that matter). Different capacity points may feature differing spin speeds and buffer sizes. For those that must know, WD admits "sub-6000 RPM operation" for the 1-TB Caviar GP (more on this on the following page).

WD argues that, like processor speeds and the associated clock speed specs that dominated CPU marketing for years, disc drive focus should move away from individual low-level specs/claims and instead focus on end results. For our part, we agree. A couple years back, we moved the StorageReview Leaderboard away from listing drives by "spindle speed class" to the current "intended use" paradigm.

The Caviar also incorporates the just-in-time (IntelliSeek) paradigm originally introduced in WD's notebook drives and "IntelliPark," a system where the drive's read/write heads are powered down and moved away from the platter assembly when not in use to reduce aerodynamic drag.

The Tests

Seagate's 1-TB Barracuda ES.2 (with 32-megabyte buffer option) and WD's 1-TB Caviar GP WD10EACS will be compared against the following drives for the following reasons:

Hitachi Deskstar 7K1000 (1000 GB)	Industry's First Terabyte Drive
Seagate Barracuda ES (750 GB)	Predecessor to the Barracuda ES.2
WD Caviar SE16 WD7500AAKS (750 GB)	Predecessor to the WD Caviar GP
WD Raptor WD1500ADFD (150 GB)	Performance-oriented 10K RPM SATA reference drive

Source: http://www.storagereview.com/1000.sr?page=0%2C1

Faceoff at One Terabyte: Seagate's Barracuda ES.2 and WD's Caviar GreenPower

2009-07-29T21:03:00.000-07:00

Leveraging a unique five-platter design, Hitachi Global Storage managed to bring the formidable Deskstar 7K1000 to the market well before competing designs. For several months now, Hitachi's beast has combined the best capacity and performance one could get on the SATA interface. Now, however, competitors Seagate and Western Digital have commenced shipment of their first terabyte units... and each manufacturer's take is a bit different from that of Hitachi's.

Seagate Barracuda ES.2

Model Number

Capacity

ST3250610NS

250 GB

ST3500x20NS

500 GB

ST3750x30NS

750 GB

ST31000x40NS

1000 GB

Lowest Real-Time Price (1000 GB, 32 MB buffer):

$152.99

The Barracuda ES.2 is the enterprise-grade version of Seagate's consumer-oriented Barracuda 7200.11 and the successor to the firm's 750-gigabyte Barracuda ES 750 (retrospectively the "ES.1"). With the luxury of a later introduction, the ES.2 manages its terabyte capacity utilizing just four 250-gigabyte platters as contrasted to the Deskstar 7K1000's five-disc design. Seagate specs the ES.2's seek time at 8.5 milliseconds.

With the ES.2, Seagate joins Hitachi as one of the first manufacturers to offer a 32-megabyte buffer on its drive as an option across the entire family's capacity. The Deskstar 7K1000's enviable performance gains suggest that the time may be ripe for the industry as a whole to move to this new level. ES.2 units featuring a more standard 16-megabyte cache are also available.

The Barracuda ES.2 is also the first enterprise-class SATA design from Seagate that will also be available equipped with a Serial Attached SCSI (SAS) interface. Slowly but surely SAS is displacing the traditional 68-/80-pin LVD interface with its vastly simplified architecture and its convenient interoperability with the mass-market SATA connection.

Seagate equips the ES.2 with a vibration compensation system typically associated with enterprise drives to mitigate performance problems that arise when many drives are packed into the same chassis and rack. The manufacturer also boasts an MTBF and error recovery rate that rival the best of the SCSI/SAS world (1.2 million hours and 1x10E-15 respectively). Seagate backs the unit with a 5-year warranty.

Also with the ES.2, Seagate commences with a newer focus on environmental concerns. Reducing power draw nets a double-edged savings through both reduced power consumption itself and reduction in dissipated heat and associated cooling costs. Seagate claims the improvements, collectively offered under its "PowerTrim" label, net a 20% reduction in draw when contrasted with the drive's predecessor... and 55% in watts-per-gigabyte when the ES.2's larger capacity is taken into account.

Source: http://www.storagereview.com/1000.sr

Western Digital Raptor WD740GD

2009-07-29T21:01:00.000-07:00

Western Digital Raptor WD740GD Capacities

Model Number

Capacity

WD740GD

74 GB

Lowest Real-Time Price:

$54.22

Introduction

Over two months ago, Western Digital provided StorageReview with a couple prototype samples of its new Raptor WD740GD, the successor to a drive that stormed its way into the enthusiast community earlier this year. Despite the lack of a key feature, tagged command queuing, the engineering sample hinted at performance not previously heard of outside the latest crop of 15,000 RPM monsters.

For more information on the drive's specs and performance potential, please review SR's Western Digital Raptor WD740GD Preview.

The WD740GD hit general availability in mid-December. Though it took much longer than hoped, the firm has finally supplied SR with production samples. This newest Raptor features a 10,000 RPM spindle speed, two 37 GB platters, a 4.5 millisecond advertised seek time, an 8-megabyte buffer, and a 5-year warranty.

Though the product itself features firmware-level tagged command queuing, at the time of this writing, no appropriate controllers were available from several likely manufacturers. TCQ will likely bring significantly better performance scaling as multi-user loads increase; as of now, however, it remains a future promise. This initial review features the Raptor operating with a Promise SATA150TX4 controller.

In the following tests, the Western Digital Raptor WD740GD will be compared against the following drives for the following reasons:

Western Digital Raptor WD740GD Beta Sample	The sample previously reviewed by SR
Western Digital Raptor WD360GD	The review unit's predecessor
Maxtor Atlas 10k IV	Current-generation 10k RPM SCSI drive
Fujitsu MAP3147	Current-generation 10k RPM SCSI drive
Seagate Cheetah 10K.6	Current-generation 10k RPM SCSI drive
IBM Ultrastar 146Z10	Current-generation 10k RPM SCSI drive
Maxtor Atlas 15k	The reigning champion for single-user performance
Hitachi Deskstar 7K250	The fastest 7200 RPM SATA drive currently available
Western Digital Caviar WD2500JD	Western Digital's current 7200 RPM SATA drive

Western Digital Raptor WD360GD

2009-07-29T20:59:00.000-07:00

Western Digital Raptor WD360GD Capacities

Model Number

Capacity

WD360GD

36 GB

Lowest Real-Time Price:

$194.75

Introduction

StorageReview.com readers have been speculating for the better part of three years on when the industry would ratchet up the spindle speed of ATA hard drives. When would it happen? Which company would start the trend? Speculation finally gave way to a real announcement on February 10th when Western Digital officially announced its Raptor Serial ATA drive.

Western Digital is in many ways the perfect company to lead ATA to a next-generation spindle speed. Ever since it introduced the Caviar WD400BB, WD has consistently led the field in ATA performance. That is a 2.5-year run at the top- very impressive in the competitive computer hardware field. More importantly, however, the firm has no SCSI business to protect. The last thing that established SCSI powerhouses such as Seagate, IBM, and Maxtor want to see is the erosion of the relatively cushy margins associated with SCSI drives. Now that WD has opened this veritable Pandora's Box, the competition is sure to follow.

According to WD, the key factor holding back higher spindle speeds was parallel ATA's lack of specification-level hot swap functionality. To be successful (initially, at least), any 10k RPM ATA drive must gun for the enterprise market. And in the enterprise, a sector that views minimal downtime as critical, the ability to seamlessly swap out a failed drive another is crucial. Serial ATA provides for such hot-swap functionality. Now that SATA is trickling into the channel, WD believes 10k RPM ATA's time has arrived.

The Raptor comes in just a single configuration- a single 36-gigabyte platter. WD specifies the drive's seek time at just 5.2 milliseconds, solidly within SCSI territory. An 8-megabyte buffer accompanies the unit. Some folks may be disappointed with the disk's relatively paltry capacity- after all, today's SCSI drives deliver 147 GB of storage in a low-profile chassis. Much like its namesake made popular by 1993's Jurassic Park, however, WD envisions Raptors in multiple-drive configurations running off of relatively inexpensive SATA RAID controllers. Reflecting its enterprise orientation, the Raptor claims a 1.2 million hour MTBF spec and features a five-year warranty.

It is important to note that the market for the Raptor is primarily the entry- and mid-level server segments and not the enthusiast desktop sector. When Western Digital raised the bar nearly 1.5 years ago, we repeatedly pointed out that the Special Edition (JB series) Caviar was what readers really wanted when they speculated over 10,000 RPM ATA drives. Equipped with an 8-megabyte buffer and accompanying firmware aggressively tuned for single-user scenarios, the WD1000JB easily matched and even exceeded the performance that the best 10k RPM SCSI drives of the era delivered when it came to desktop performance. While SCSI disks feature superior mechanics, their server orientation forces them to trade away firmware optimized for highly-localized patterns in favor of strategies that maximize returns in random access scenarios. In the Raptor, WD faces much of the same quandary. With its enterprise-class warranty and seek time, however, the firm attempts to target server markets.

Initial tests run on a pre-production sample supplied by long-time sponsor HyperMicro yielded disappointing results. Immediately afterwards, however, Western Digital was eager to get a production-class unit in our hands. Retrospectively, there were three key factors that prevented the beta sample from achieving maximum performance. First was the lack of write caching, especially apparent by the model's poor showing in the SR High-End DriveMark 2002, a pattern that emphasizes write performance. Secondly, the pre-production drive utilized platters that were not optimally low-level formatted. Lastly, the drive suffered from an older firmware revision.

The production sample, of course, addresses these concerns. Our initial beta sample figures were drawn in conjunction with a Promise SATA TX4 controller. Though we also ran tests with a Silicon Image 3112A chipset, the combination resulted in exceptionally poor results likely arising through some unpredictable interactions between the drive's firmware and the SI chipset. The production unit, fortunately, does not exhibit the same problems. Though Promise's controller delivers superior results with the Raptor, we have presented results with SI's chipset due to its prevalence in the controller market.

Source: http://www.storagereview.com/WD360GD.sr

Western Digital VelociRaptor WD3000BLFS

2009-07-29T20:55:00.000-07:00

Western Digital VelociRaptor WD3000BLFS

Model Number

Capacity

WD3000BLFS

300 GB

Lowest Real-Time Price (300 GB):

$264.48

Encompassing three generations of releases, Western Digital's standout 10,000 RPM Raptor family has been warmly received by enthusiasts worldwide over the course of the last five years. Combining the best single-user performance money could buy with a relatively reasonable price, each Raptor release satiated enthusiasts with a marriage of increased capacity and over-the-top performance. Perhaps the largest complaints leveled against the series have been the large swaths of time separating each release.

Though WD rapidly followed up its initial 37 GB release with a significantly improved 74 GB model, almost two years separated the Raptor WD740GD and its successor, the Raptor WD1500ADFD. As the family's first native SATA design, the latter Raptor again stood as WD's performance-oriented offering for nearly sixteen months. In that time, terabyte behemoths hit the channel and have chipped away at and in some cases even surpassed the venerable third-generation Raptor in sheer performance. Its 150-gigabyte capacity also seemed more and more constricting as the months ticked by.

WD has finally addressed the issue and unveiled its fourth-generation design. Dubbed "VelociRaptor," this newest entry ups the family's flagship capacity to 300 gigabytes and introduces a host of fundamental changes. Though we suspect that much if not most of the Raptor's success has come from the enthusiast sector, WD has not forgotten its desire to see the Raptor penetrate the enterprise server market. In a nod to the emerging smaller form factor initiated by Seagate's Savvio design, WD has moved the Raptor series to a 2.5" chassis.

The majority of today's desktop machines still expect standard 3.5" drives. While some users seeking the ultimate in acoustic and thermal performance have taken to mounting notebook-oriented 2.5" designs into their home rigs, the consumer world remains a 3.5" landscape. Many readers have found out that desktop cases, 2.5" drives, and rails that convert such units to 3.5" form factors don't always get along. Screw holes frequently fail to line up and necessitate custom solutions such as drilling to get everything aligned.

WD has addressed the issue by outfitting initial shipments of the VelociRaptor in a custom 2.5" to 3.5" converter. Dubbed IcePAK, this aluminum chassis permits the drive to be mounted in any standard 3.5" bay. Though it's somewhat stylishly cut with heatsink-like fins, IcePAK's purpose is primarily form factor conversion, not heat distribution. It should be noted that an IcePAK-mounted VelociRaptor does not perfectly mimic a true 3.5" drive when it comes to rear-connection alignment; IcePAK drives won't work with the standard SATA/SAS backplanes found in many rack-mounted servers. Standard SATA cables, of course, work just fine. For enterprise use, the firm plans to ship VelociRaptors sans the 3.5" chassis.

The VelociRaptor's 2.5" design, as one would expect, incorporates two reduced-diameter platters packing 150 gigabytes each. The narrowed span leads to a manufacturer-claimed seek time of just 4.2 milliseconds, a 12% improvement over that of the WD1500ADFD.

Though a roomy 32-megabyte buffer accompanies some of today's terabyte drives, WD has chosen to stick with a more conservative 16 MB cache. In contrast to the 1.5 Gb/sec-equipped WD1500ADFD, the VelociRaptor represents the first iteration of the family to ship with a 3 Gb/sec SATA interface. Reflecting the series' continued enterprise-orientation, the WD3000BFLS ships with a claimed MTBF of 1.4 million hours and a 5-year warranty.

Source:http://www.storagereview.com/WD3000BLFS.sr

Get Your Laptop Hard Drive - 2.5" Great Performance

2009-07-29T19:56:00.001-07:00

Hard drives don't just came at a different capacitance points, but they be given at different rotary motion accelerates that affect information transferee accelerates and memory access times, and at that place is more technological points to consider. Our fresh interactional graphs as 2.5" notebook computer disc drive allow for a great overview about the quickest drives, or the driving force that will give way you the better bang for the charge. We take in benchmark issues in different classes for a general amount of products, whether this are central processing unit, graphics cards or hard drives. The destination is to provide the almost comprehensive performance comparing servicing on the online. Become to the 2.5 "disc drive graphs at once or find out some primary information about how to take the good notebook computer disc drive on the followers

All adamantine drives are created equal: They abundance abstracts on one or several alternating alluring platters. So-called active attract microscopically baby areas on the discs to address bits. These are accumbent concentrically,these circles are refered to as tracks.

Two factors accept a cogent appulse on the acquirement accommodation of a adamantine drive: drive accommodation and performance. Issues such as operating noise, temperature or ability burning are interesting, but usually alone of abundant accent to a bound cardinal of users and applications. 4,200 RPM drives are about silent, and those spinning at 5,400 or 7,200 RPM about can alone be heard alone as continued as the CPU fan does not bang in.

Notebook users can accept amid lots of altered 2.5" drives in capacities alignment from 30 to 160 GB. The alternative includes 4,200, 5,400, and 7,200 RPM models, with UltraATA/100 or Serial ATA/150 interfaces. Be accurate with ultra carriageable notebooks, though. Models such as the Dell X1 or Samsung's Q30 ancestors are based on tiny 1.8" adamantine drives. These crave beneath ability and space, but their achievement is appreciably worse, which you will calmly apprehension in accustomed assignment with such a device.

While best users accede accommodation only, we acerb acclaim demography a abutting attending at achievement ambit as well. Choosing a faster adamantine drive will accomplish your circadian assignment added affable than will accepting a few added gigabytes. The somewhat college activity burning of faster spinning drives is usually compensated for by finishing read/write tasks abundant quicker. In the end, the array run time of notebooks application accelerated adamantine drives is not appreciably beneath than that of models with slower drives.

Currently, 7,200 RPM drives are accessible at up to 100 GB, while 5,400 RPM ability all the way up to 160 GB. If you intend to use your anthology intensively, we acclaim activity for annihilation beneath 7,200 RPM. All added users should baddest a 5,400 RPM drive; 4,200 RPM models should be abhorred as they are slower and at this point, accommodate little to acclaim them.

Anatomy of a Hard Disk Drive (2)

2009-07-22T20:44:00.000-07:00

by: http://www.hardwaresecrets.com/

Logic Board

On the logic board you will find all circuitry in charge of controlling the hard drive. In these days of highly integrated devices, you will find just three or four big integrated circuits on the logic board, as you can see on Figures 4 and 5. Take a look on the pictures as we will explain more about the circuits pictured below.

click to enlarge
Figure 4: Logic board from an ATA hard drive.

click to enlarge
Figure 5: Logic board from a SATA hard drive.

The big circuit is the controller. It is in charge of everything: exchanging data between the hard drive and the computer, controlling the motors on the hard drive, commanding the heads to read or write data, etc.

Optionally there is a Flash-ROM circuit where the hard drive firmware is located. Firmware is the name given to a program that is stored inside a ROM (Read Only Memory). The hard drive firmware is the program its controller executes. Sometimes this device is embedded in the controller, as it happens on the hard drive on Figure 5.

The controller doesn’t drive enough current to turn on or move the hard drive motors. So all hard drivesuse a motor driver chip. This chip is a current amplifier. It takes the commands sent from the controller to the motors and passes them to the motors, but with a higher current. So, this chip is located between the controller and the motors.

The fourth main chip you can find on a logic board is the RAM (Random Access Memory) chip, also known as buffer. This chips has an ultimate role in the hard drive performance. The higher its capacity, the fastest the data transfer between the drive and the computer will be. You can find out the capacity of your hard drive buffer on the chip manufacturer’s website. For example, the memory chip on Figure 4 is a Hynix HY57V161610DTC chip. Going to Hynix’s website at http://hynix.com/datasheet/eng/dram/details/dram_01_HY57V161610DTC.jsp you can find this is a 16 Mb (Megabit) chip. The capacity of memory chips is given in Megabits, while we use Megabyte to refer to memory capacity. Thus we need to divide the value given in Megabit by eight in order to have the value in Megabyte. So, this chip is a 2 MB (Megabyte) chip, so this hard drive buffer is of 2 MB.

On Figure 5 you can see another chip, which is a SATA/ATA converter chip. A lot of manufacturers instead of designing Serial ATA controller chips simply pick ATA controller chips and add a converter chip to convert the hard drive Serial ATA interface into regular ATA. This is the case of the hard drive on Figure 5, which uses the Marvell 88i8030 converter chip. So even though this hard drive has a Serial ATA interface, it is not a “true” Serial ATA hard drive (it is not a “native” Serial ATA hard drive), since its controller chip is still ATA.

You may be wonder how do we know the function of each chip on the logic board. Actually it is fairly simple and you can learn the trick from us. Just type in the numbers located on the first line of the chip package on Google and it will return a lot of information about the chip! For example, for the Flash-ROM used on the hard drive on Figure 4, just type in M29F102BB and the first item returned will be a page on ST Microelectronics with all technical details of this chip.

Spindle Motor

On Figure 6 we show the H.DA after we removed the logic board. There you can clearly see the spindle motor and its contacts – which connect this motor to the logic board –, and also the contacts from the devices inside the HDA, namely the heads and the voice coil actuators.

click to enlarge
Figure 6: HDA without the logic board.

On hard drives targeted to desktops, the spindle motor rotates at 5,400 rpm, 7,200 rpm or even 10,000 rpm, depending on the drive. The faster this motor rotates, the faster data can be read from the platters. Hard drives targeted to laptops usually rotates at 4,200 rpm.

Inside the HDA

We removed the hard drive cover to show you how it looks like inside. Do not do this with you hard drive or you will damage it. If you are curious, open only defective hard drives (our hard drive was defective).

click to enlarge
Figure 7: Main parts inside a hard drive.

The connector you see on Figure 7 is the opposite side of the connector on Figure 6.

The hard drive can have several discs. The one on our picture had three discs. There is one read/write read for each side of the disc – which is also called platter. The heads are stuck together in an arm. So, all the heads move together.

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Figure 8: Several discs inside a hard drive.

A motor (actually the correct term is “actuator”) called voice coil moves the arm. It is called “voice coil” because it uses the same idea behind loudspeakers: a coil inside a magnetic field provided by a magnet. Depending on the current direction on the coil the arm moves to one side or to the other side. And depending on the intensity of the current, the actuator will move more or less. We removed the top “cover” (actually the top magnet) from voice coil and you can see it disassembled on Figure 9.

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Figure 9: Voice coil actuator.

We removed the arm from the hard drive. You can see it on Figure 10. While we were removing it, we broke one of the heads (ops!). So, it should have six heads there but you will only see five (sorry, chief!)

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Figure 10: Hard drive heads.

Anatomy of a Hard Disk Drive (1)

2009-07-22T20:18:00.000-07:00

by: http://www.hardwaresecrets.com

We disassembled a hard driveto show you the main components you will find on a hard drive.

Hard drives have two kinds of components: internal and external. External components are located on a printed circuit board called logic board while internal components are located in a sealed chamber called HDA or Hard Drive Assembly.

You cannot open a hard drive or you will make your drive unusable. Hard drives are assembled in clean rooms (cleaner than surgery rooms) and then sealed. Any particle of dust inside the HDA can destroy the surface of the discs, because the discs spin at a very high speed (at least 5,400 rpm nowadays). This would not only lead to data loss, but also the physical destruction of the disc surface.

So, there is no serviceable part inside the HDA – at least for the regular technician. Only data recovery companies with clean rooms can open and replace components inside the HDA.

Anyway, before exploring the components located both the logic board and inside the HDA, let’s take a look on the connectors found on a regular hard drive.

Connectors

Hard disk drives have basically two connectors, one for power and other for exchanging data with the computer. This second connector is better known as “interface”. The most common hard disk drive interface for end-users is called ATA (Advanced Technology Attachment), while SATA (Serial ATA) interface was created to replace ATA and is becoming more popular these days. After the released of SATA, ATA interface started being also called PATA (Parallel ATA). Another famous interface is called SCSI (Small Computer Systems Interface), but it is targeted to servers and rarely seen on PCs targeted to end-users.

Figure 2: Connectors on a hard disk drive using ATA interface.

The master/slave jumper on ATA hard drives can be configured in three different ways:

Master: this means that this drive will be the only one attached to the cable that connects the hard drive to the computer or will be the first drive in a two-drive configuration.
Slave: this means that this drive will be the second drive attached to the cable that connects the hard drive to the computer.
CS (Cable Select): this means that you will use a “special” cable (called CS cable) that the configuration of whether a drive will be master or slave will be made by the position of the hard drive on the cable and not by a jumper configuration on the drive.

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Figure 3: Connectors on a hard disk drive using SATA interface.

Serial ATA standard introduced a new power supply plug, which is very different from the standard hard drive power plug. Since Serial ATA is still entering the market, you will find a lot of Serial ATA hard drives with both power connectors, like the one on Figure 3. You need to use just one of them, not the two at the same time.

To learn more about ATA and Serial ATA, we’ve written a complete tutorial on ATA drives and a complete tutorial on Serial ATA drives.

Let’s move on and talk about the components on the logic board.