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No. most manufacturers define the terms as 1024 bytes per kilobyte, 1000 kilobytes per megabyte, 1000 megabytes per gigabyte, and 1000 gigabytes per terabyte. Which gets really confusing sometimes - they can't even stay consistent within their own system.

I haven't checked how Hitachi does it, but that's how Seagate and Western Digital do it. I would assume Hitachi marks them the same way.

No, actually, you're completely wrong.

Hitachi (click Specifications):

Capacity - One GB is equal to one billion bytes and one TB equals 1,000GB (one trillion bytes) when referring to hard drive capacity.

Seagate:

When referring to hard drive capacity, one gigabyte, or GB, equals one billion bytes and one terabyte, or TB, equals one trillion bytes.

Western Digital (click Specifications):

As used for storage capacity, one megabyte (MB) = one million bytes, one gigabyte (GB) = one billion bytes, and one terabyte (TB) = one trillion bytes.

Some floppies use hybrid measurements, but hard drives have been entirely powers of ten for ages.

For some reason when I read the summary (no, not TFA) I envisioned the "Get Perpendicular" video and now I have that damned song stuck in my head. Gee, thanks a lot, Slashdot.

Is changing the spindle speed the same as adjusting the IDE acoustic mode? I'm looking for an entry in the IDE spec because I had no idea that rotational speed is software selectable on some drives. Thanks...

Hitachi's tool for setting speed. If you look at how that works it might point you in the right direction.

Alright AC - you gotta include the link to the Hitachi animation to get mod points for that comment. like so

Well, Hitachi, the company bought their HD business made a good name in hard disks. So, the management and perhaps software outsourcing was the issue.

They still use "Deskstar" brand FYI.

http://www.hitachigst.com/portal/site/en/products/deskstar/

Too bad all major HD manufactures claim 10,000 power cycles, and many power saving settings will turn off a HD w/o doing anything else.

That number sounded wrong, so I checked some typical 3.5" desktop hard drives. These are the first three I looked at.

Seagate 7200.10 : 50 000 start/stop cycles.
WD Caviar Blue : 50 000 start/stop cycles.
Hitachi Deskstar T7K500 : 50 000 start/stop cycles.

Since Seagate bought Maxtor and Hitachi bought IBM's storage division, those three are all the major manufacturers of desktop hard drives.

Head wear is the limitation with stopping and starting typical desktop hard drives. Desktop drives typically park their heads on a laser-etched landing zone at the centre of the platters. Spinning up the drive causes wear as the heads drag on the surface until the air cushion is developed - the laser etching roughens the surface, allowing the heads to slide more easily. Most laptop drives park their heads on a ramp, so the platters can spin up with no head contact and can take an order of magnitude more cycles (specified as load/unload).

This is one of those commonly held beliefs that has absolutely no facts behind it.

The data sheet for my Hitachi HDS721075KLA330 drive rates it at 50,000 load/unload cycles. If it powered up 50 times a day (which would be quite possible in a desktop with aggressive power savings enabled), it's specced to last about 3 years.

From a mechanical standpoint, this belief also does not make any sense.

The people who actually built it seem to disagree with you. Hint: a spinning hard drive takes little energy to stay in motion. A stopped hard drive takes quite a bit of torque to spin up to running speed in a small number of seconds.

That's because you don't have one of those new perpendicular recording hard drive. Every time I load or save a file, I hear disco music.

My 2-year old loves it...

http://www.hitachigst.com/hdd/research/recording_head/pr/PerpendicularAnimation.html

Here you go! http://www.hitachigst.com/hdd/research/recording_head/pr/PerpendicularAnimation.html

Get Perpendicular

If you haven't seen it, it's School House Rock meets How It's Made meets Engineering 101. Very cool stuff.

Fluid Dynamic Bearing Spindle Motors: Their future in hard disk drives

Hitachi has already implemented the "incorrect" version for a number of years now:

From their Feature Tool User's Guide PDF:

APM is a technology that adaptively adjusts the power saving feature of New Hitachi and Legacy IBM hard disk drives to suit your working style. Power is saved by idling the actuator arm, additional power is saved by unloading the actuator arm and heads from the disk to the off-ramp. The technology actively adjusts the trade-off between disk delay and power consumption. This program allows you to change the aggressiveness of the power saving.

I have a few old (2005) Hitachi Deskstars and I tried out this utility. What happens is when the disk determines it has been idle, the disk will (on it's own, no BIOS or OS intervention) lock the head and spin down the disk but not stop the disk completely. You can actually hear the head lock itself with a "click" sound and the drive noise lowers since the disk doesn't rotate as quickly. When you start reading from the disk again, it spins up quickly and reads/writes in about a second or two. When measuring total system power, when the disk went into a low power state, the system power went down 3 to 5 watts.

I don't know enough about hard drives to know why they don't have variable read speeds and why the head needs to be moved off of the platter when the disk spins down

PMR got almost nowhere because all the R&D funds got through PR first and all we got was this funny cartoon.

1 CPP-GMR: As an alternative to existing TMR heads, CPP-GMR head technology has a lower electrical resistance level, due to its reliance on metallic rather than tunneling conductance, and is thus suited to high-speed operation and scaling to small dimensions.

2TMR head: Tunnel Magneto-Resistance head A tunnel magneto-resistance device is composed of a three layer structure of an insulating film sandwiched between ferromagnetic films. The change in current resistance which occurs when the magnetization direction of the upper and lower ferromagnetic layers change (parallel or anti parallel) is known as the TMR effect, and ratio of electrical resistance between the two states is known as the magneto-resistance ratio.

Source: Official Press Release

I *think* this may be the drive.

Flip to page 13 and read along with me:

• Start up: 4.5W
• Idle: 0.65W
• Low Power Active: 1.65W
• Seek: 2.25W
• Read / Write: 2W
• Standby: 0.25W
• Sleep: 0.1W

The more you know!

not always..

http://www.hitachigst.com/hdd/research/recording_head/pr/PerpendicularAnimation.html

Perpendicualr Recording came out very very very fast after it's concept.. hell i want to say it was less than 3 months between release of idea to owning a drive with that tech.

YMB(R)NH (You Must Be (Really) New Here)

The obligatory reference for HD density stories is Perpendicular

Hitachi_Hard-Drive_Project_-_Noriko_Version.mp3

Written by James Postlethwaite, whose home page I can't find, and made entirely out of hard drive failure noises (Hitachi provide a nice set of wavs).

Use the scientific term for it. Haven't flash animations from Hitachi taught you anything?

We all know the real reason here. It's all those perpendicular bits on the dance floor getting drunk and falling down.

They were all fairly calm when this footage was shot but the wildness ensued soon after.
http://www.hitachigst.com/hdd/research/recording_h ead/pr/PerpendicularAnimation.html

Perhaps you've heard of perpindicular recording, which started early last year. Pretty soon it's going to be impossible to get a hard drive that doesn't have this new technology. You can easily argue that the technology can't go anywhere after this, but it does offer a 10x storage density increase, and you know somebody will be cramming more data blocks on a platter soon enough.

Blasphemy. No mention of perpendicular recording is complete with out a link to this.

Talking about bizarre presentation of technology, nothing beats a singing ensemble of hard drive parts and bits.

I thought you were full of it, but, http://www.hitachigst.com/hdd/library/whitepap/gla ssdisk/whiteglass.htm. Interesting.

Surely they need to cool the components in the middle of the stack?
Unless they decide to leave some of the holes open then anything in the middle is going to overheat?

I always imagined this kind of tech running on some kind of multi layered wire fence with plenty of room for cooling.

Incidentally, didn't Hitachi beat them to the whole 3d element thing?
http://www.hitachigst.com/hdd/research/recording_h ead/pr/PerpendicularAnimation.html

Ohh, it's perpendicular!

Obligatory link.

Startup current: 2.0 A on the +12V rail, plus 1.4 A @+5V

Power - Random R/W (avg): 13.6 W

(heat dissipation equals the power consumption, since there is no "output power")

Power consumption is mainly a function of the number of platters (5 in this case) which in turn determines head assembly inertia, and seek time (inversely). In any case, the inertia of one motor and hub plus five platters is surely less than four such assemblies with 2-3 platters each.

As for noise: does anyone have an idea of how loud is 2.9-3.2 bels (typical) ?

"50GB HDD: A nice upgrade from the 500GB ones? Sure. An innovation? Well, the number is bigger than it was last year."

Two words: Get perpendicular

I believe that the 750 gig drives were considered innovative because the 750 gig drive were the first to 'get perpendicular'.

You bring up a good point, and I would agree but for the "mobile" factor.

You can still crash an iPod by throwing it across the room, (same goes for any HD) but not so with an iPod Nano. It will take bump after thump and still keep playing.

You can't beat zero-moving-parts for stability.

Then again, there are advances in "shock proofing" hard drives; Hitachi has led the way in zero-G sensors (parks and suspends the drive within 4" of being dropped) and now Plextor has their alleged "shock-proof" portable drive. (though it has been de-bunked in this extreme testing experiment shows) So much for empirical terms in marketing.

First, I must say that get perpendicular animation by Hitachi is awesome. http://www.hitachigst.com/hdd/research/recording_h ead/pr/PerpendicularAnimation.html

To explain this topic a little better I am posting a recent paper I wrote. Its posted in PDF, under the creative commons liscense @ thinkfree.com

File http://www.thinkfree.com/filelink.tfo?filemasterno =551951&filekey=00odg0wy0z
Published http://www.thinkfree.com/common/view.tfo?method=vi ewPublish&uid=89152&fno=551951

Below is an except.
Using Quantum Vortex Cores To Defeat
The Superparamagnetic Effect In Magnetic Storage

One could argue that few new types of data storage devices have been invented. Traditional data storage exists in rings rotating around a disc. First in the analogue realm with the advent of the record player. Then came the digital realm which gave symbolic meaning to magnetic polarities on hard disk drives. As humans pursue the path of miniaturization, we find that the stability of our newtonian devices are being affected by what is predicted with Quantum Theory. Designs exploiting the properties in the quantum realm must be accomplished. Recent development shows, that it is within our capability to measure and systematically alter the spin direction of a single atom, when contained in a Lanau structure. The Quantum Vortex Core refers to the magnetic field created perpendicular to the direction of spin. Quantum Vortex Cores retain their polarities, allowing us to advance in data storage.

A brief understanding of Hard Disc Drive (HDD) technology and its limitations need to be known before Quantum Vortex Core can be understood in its application. For the last 50 years the HDD has used a method called longitudinal magnetic recording. Circular tracks make rings around the radius of a platter containing magnetic bits oriented north or south to the direction the platter spins. A device called an actuator has an inductive coil on its tip/head which converts electrical pulses into momentary magnetic fields. A certain layer of materials on the platter retain their magnetic orientation set by the write head. As the platter spins, the write head is positioned over the next bit. This process is reversible, and the data can be read by monitoring the electrical pulses coming from the similarly designed read head when passing over changing magnetic fields.

HDD are designed to shield from external magnetic fields, since common external magnetic fields exceed the 'crystalline anisotropy energy' needed to purposefully retain the orientation of the bits. Heat also plagues the stability of the data retained when energy from ambient temperature reaches the 'crystalline anisotropy energy' level (Nguyen). Until recently, this energy level has been ignored since the magnetic bits were significantly large enough to need exceedingly high temperatures to affect their base state, from which they will not move. As we approach miniaturization the energy to reach the crystalline anisotropy energy level becomes less. The field energy stored in each bit around the platter, begin to re-orient their neighbor bits; when this happens it is said to have reached its superparamegnetic limit (Public Domain).

Since the opposites attract / likeness repel effect plague miniaturized HDD when the bits are laid end to end. It only seems reasonable to reorient in such a way which they do not interfere. If the bits were positioned perpendicular (standing up on the disc) rather than laying flat, one also increases the data density as well as limiting the superparamegnetic effect (Hitachi). Perpendicular storage seems reasonable, but proves difficult, and

I'm totally down with it!

Get Perpendicular!

Get Perpendicular!

The 160 GB drive is the Hitachi Travelstar 5k160. This disk uses perpendicular recording technology which claims to produce 30% improved performance over older technology. According to one source, this technology increases both storage capacity (data density per unit area on a platter) and subsequent performance because more data can be moved within a given area no the platter. So, a 30% boost to a 5400 rpm system, all else being equal, would be about like having a 7020 rpm drive. This is pretty close to 7200 rpm if this logic holds.

Additionally, these drives consume less energy and run cooler. These are two other, very important to consider with a laptop. It will be interesting to see how the performance figures (including thermal performance and battery life) compare between these drive options on otherwise identical machines.

"Did you know perpendicular recording for hard disks was developed in 1976 but is only now being implemented?"

1976, eh? That's explains a lot about this thing, then.

Yeah, because the hard drive is the new bling.

Fullscreen that funk!

http://www.hitachigst.com/hdd/research/images/pr%2 0images/Get_Perpendicular.swf

Remember, Get Perpendicular

Hitachi has been doing research in this area for years. They are very good at representing complex systems visually. Check it out http://www.hitachigst.com/hdd/research/recording_h ead/pr/PerpendicularAnimation.html !

I thought the next limiting factor for hard drive densities was the limits of physics with respect to magnetic materials? So there's no need to get perpendicular?

http://www.hitachigst.com/tech/techlib.nsf/techdoc s/9F13D129F76896D08625701500774BD2/$file/Viper_SAS _Specv1.4.pdf

Seems to disagree with you. There are no 15,000 RPM 2.5" drives, and only a couple of 10K 2.5" drives on the market right now

Average seek of 3.6ms, sustained data rate of 93.3MB/sec... All in a nice little 2.5" package.

Umm... Maybe you misread that. It's over an inch tall, and 4"x5.7", according to its spec sheet. That would make it, by necessity, a 3.5" form-factor hard disk. It is nice, though. Now I just have to get a machine that can use SAS drives well, and save up a lot of money. I've got a 15kRPM Fujitsu hard disk around here somewhere that a customer gave me, but I never got around to shelling out the money for a Ultra320 controller so I could use it. C'est la vie.

You knew it was coming!

"This high capacity is made possible by perpendicular recording, a technology which records data on the hard drive perpendicularly instead of longitudinally,"

http://www.hitachigst.com/hdd/research/recording_h ead/pr/PerpendicularAnimation.html

The average cost for the drive under review is around $200, which isn't bad. What I think is interesting is the cost behind setting up, say, a 4 Element SRAID system with these. Could heat be a problem here?

Whatever the answer, the advance of smaller (physically) but larger (storage) has arrisen from perpendicular recording on the discs, which is itself a cool find.

Hey, when your reaching the maximum density, you know what you gotta do don't you?

You get Perpendicular :)

I instantly thought of this when thinking about the Intel thing.