LOL, seagate doesn't dare offer more than 2 years on anything but "enterprise" grade. I wonder if they really have confidence in those products, or merely priced them twice as high as normal, so you are effectively buying two drives at once - the one you are gonna get right away and the one they will send for a replacement when it fails.
If by "a lot of their products" you actually mean ONLY their entry-level bottom-line conventional Blue series, you're right. In their current lineup that's the only thing with a 2-year warranty. The Blue SSHD, standard Red, WD AV, and Purple series all carry a 3-year warranty. Their Red Pro, Black, and VelociRaptor series have a 5 year warranty. That's obviously not counting Enterprise-focused series which all carry a 5 year warranty except the Cold Storage Ae series which is still 3 years.
Facts aside I might be biased because the majority of hard drive failures I've seen or dealt with have been Seagates, with the exception of a particular series of Deskstars which thankfully was not a mistake they repeated (later-gen designs after that were very solid). I also had great luck with Fujitsu, and was a bit sad to see them snatched up by Toshiba. So goes the shrinking HDD universe.
Ditto. I have RMA'd so many Seagate laptop drives that I don't even bother anymore and just replace them with Mushkin SSDs. Same goes for garbage Hynix memory modules. Dell fills their product line with these junk brands.
The equivalent of the WD Red is the Seagate NAS HDD. It has a 3 year warranty. The equivalent of the WD Purple is the Seagate Surveillance HDD. It has a 3 year warranty. The equivalent of the WD AV is the Seagate Video HDD. It has a 3 year warranty. The equivalent of the WD Red Pro is the Seagate Enterprise NAS HDD. It has a 5 year warranty. The only ones Seagate doesn't have an equivalent for that you listed is the WD VelociRaptor and the WD Black. On every other one of their products they have the same warranty as WD.
So... If they can manage to hermetically seal in Helium, why not go the extra mile and just hermetically seal a vacuum? Surely, platters/heads moving in near-total absence of any gases at all would require even less power? And it's not as if the task if maintaining a vacuum seal in the face of a single atmosphere's worth of external pressure is all that insurmountable: vacuum thermoses have been around for nearly a century - https://en.m.wikipedia.org/wiki/Vacuum_flask
Because the heads ride on a cushion of air that prevents them from crashing into the platter. If you had a vacuum then the slightest vibration would cause a head crash and destroy the drive.
Also, with vacuum you'd have to sustain constant outer pressure on the component at 100kPa... With vacuum you are getting to a completely different league in all steps - sealing, venting, cover pressure resistance, heads "gyroscope" thing you'd need to have and lots of other things I can't even think of :-)
"no big deal" is not entirely correct here, Helium is widely used as a measurement tool for leak rates, because it will leak faster and through smaller gaps than any other gas except for hydrogen. So to ensure a constant Helium pressure within a case (that may cycle in temperature quiet regularly) for 5 years is non-trivial.
But yeah, still easier than vacuum. Which would lead to instant evaporation of normal lubricants as well, so you would have to replace the mechanism by something vacuum capable with a dry lubricant.
@jabber: "Actually maintaining a vacuum is easier than trapping helium long term."
True. It is easier to keep an enclosure sealed against a nitrogen and oxygen leak than a helium leak, so maintaining a vacuum is easier than trapping helium long term. However, operating mechanical parts in a vacuum is not. The two big hitters that come to mind are how vibrations affect moving parts at small distances with no air cushion (think head crash) and how you keep joints and spindles from seizing up (liquid lubricants don't hold up in vacuum). I'm not sure dry lubricants are practical at normal HDD spindles speeds either.
-- True. It is easier to keep an enclosure sealed against a nitrogen and oxygen leak than a helium leak, so maintaining a vacuum is easier than trapping helium long term.
I'd like to see the equations on that, since this amounts to the assertion that He at standard temperature and pressure (at least, that's what current reporting states) inside a vessel will more easily escape a seal out of the vessel than atmosphere will breach a seal from outside a vacuum vessel (vessels engineered to contain/block passage).
The helium goes straight through the metal because of how small the singl-atom molecules are (they fit between the atoms of the metal and go straight through..). Every other element has a bigger molecule in comparison and has a much harder time going through materials.
I have trouble with that notion (of heads riding on a 'cushion' of air.) If anything, there are complexities of turbulence caused by friction, head movements, acoustic resonances - that would induce chaotic vibrations to begin with. And if Bernoulli physics have not yet been repealed, I'd expect the air near the platter to be moving faster (due to platter-air friction tugging it along) than air at the midpoint between platters - and faster moving air means lower pressure. Which would imply that the air dynamics would actually act to pull the heads toward the platter rather than 'floating' them - so the heads would have to incorporate some kind of an airfoil-like wing just to counter that force. Which introduced yet more friction and turbulence losses/instabilities into the system.
I have trouble with people posting giant paragraphs about how they don't understand engineering or physics and doubting the factual statements made by more knowledgeable posters.
Try to be scientific and curious. Instead of spouting all this pseudo science (are you trying to convince us you are smart?), just go google it. You will quickly learn that drive heads ride on a cushion of air as stated. In the face of actual facts go reread your post and be humble and curious next time.
This may sound harsh to you, but it will help you in your job and life if you have a curious "I want to learn" attitude.
-- Air cushioning of the heads have been a known fact for as long as winchester-based DASD has existed.
longer actually. IIRC, the first DASD from IBM mainframes exploited "floating heads", at least the 1301 drive. that was 1961: "The 1301 is the first disk drive to use heads that are aerodynamically designed to fly over the surface of the disk on a thin layer of air."
I really don't see what he's doing so wrong. He has some knowledge that makes him think one thing, and he's presented with information that conflicts with that, and he's trying to reconcile the two. Really, the conclusions he's drawing do seem reasonable, even if they're incorrect.
As far as googling it, it's not as easy as it sounds. Sure, it's easy to find stuff saying that the head rides on a cushion of air, but I wasn't able to find much explaining the phenomenon, i.e. the mechanism by which the air bearing forms or how it acts as a cushion. So if you're as knowledgeable about engineering and physics as the condescending tone of your post implies, would you care to try and explain, or provide a source that does?
He's not spouting pseudo-science. What he's describing is exactly what happens with an incompressible fluid like water. It's why ships need tugboats to push them away from docks - they can't do it under their own power (unless they have a bow thruster), since any forward or backwards movement just pushes them closer to the dock. The QE2 ran aground partly due to this effect (high speed over shallow water caused it to be "sucked" down by Bernoulli forces). https://en.wikipedia.org/wiki/Squat_effect
Air (and helium) however are compressible, which leads to a different phenomenon (ground effect) which counters Bernoulli.
You forget what would be causing the gas to move at all:the platter. The gas is actually caught by the platter as it spins, sucking it under the heads.
If you lay a piece of paper on a table, lift one side, and try to blow under it, it won't magically stick harder to the table. Yes, there is air moving, but you can't overcome displacement. The pressure is actually higher as it is being compressed/forced, and the movement is alleviating the pressure.
Sucking is probably a bad way to describe it... The platter actually pushes the air it contacts, which increases pressure under the heads and creates the cushion.
@sor: "The platter actually pushes the air it contacts, which increases pressure under the heads and creates the cushion."
Which is possible because air/helium is compressible. In fact, it is this compressibility that stabilizes the heads. It makes it act as a shock absorber of sorts.
@Solandri: " What he's describing is exactly what happens with an incompressible fluid like water. ... Air (and helium) however are compressible, which leads to a different phenomenon (ground effect) which counters Bernoulli."
This. The Bernoulli effect doesn't disappear, it simply ceases to be the dominant force. Interestingly, IIRC, it actually helps dampen vibrations by resisting the repulsing part of the vibration.
As far as I know you're correct - the only piece missing is that the heads are indeed aerodynamically designed to provide the proper force repelling them from the platter. That's what Azethoth described in fancy scientific language ("riding the cushion of air").
Your critical flaw is the misguided use of Bernoulli's principal. Bernoulli's principal is actually derived from Navier-Stokes through certain assumptions, which are not applicable here. What we're actually looking at in the case of spinning platters is a Couette flow, where a velocity is created through shear forces in the fluid and NOT a pressure gradient. There is no pressure gradient in the tangential direction.
That's a pretty good recollection of physics - just enough to get you into trouble. What you're describing happens if the fluid is a liquid. We ran into it all the time with our robot submersibles - if you get too close while running parallel to a wall, the submersible gets "sucked" against it by Bernoulli forces and you're stuck (need to turn so a thruster can push you away... if you have enough room to turn).
It's different when the fluid is a gas. At moderate distances, Bernoulli rules. But as the two surfaces get very close, the compression of the gas as it squeezes between the head and platter overpowers Bernoulli, and you get a high pressure zone. In aircraft, it's called ground effect, and can be used to greatly extend cruising range because the higher pressure between the wing and ground (or water) creates more lift, reducing drag.
One problem that you have not realized ... The cushion is caused by the platter spinning... Not by the drive head spinning... Your understanding of physics is limited to airplane wings, because what your have described is an airplane wing moving through air...
P.S. If I had a goal of preventing read/write heads from crashing into platters in a vacuum enclosure, I might look into giving both the heads and the platters a matched electrostatic charge (i.e. both positive, or both negative) so that they repel each other - and do so more strongly the closer they get. Only issue would be calibrating the charge strength against the magnetic field induced by charges in relative motion and the resistivity of the storage medium (so the stored data doesn't get mangled by the mere act of spinning the platter past the moving head.)
You are totally dazzling me with your HDD building prowess. Is there a twitter feed I can subscribe to? Are you going to start your own vacuum HDD company with auto erase as you read and write technology? Can I get shares now?
Ah brilliant, that would just recreate the original problem again, put some force on the disk in a lopsided manner then spin it. This time by using charges that conveniently erase disk sectors as the disk rotates. How many RPM will it take before that disk wobbles out of control or tears itself apart I wonder.
You really think the engineers working for the company are that dense as not have thought about that? The hard drive industry have been around of decades. I think they know a thing or two about the intricacies of building a hard drive by now ....
A vacuum isn't the same as Helium. Its more than just the reduced drag of using Helium. Read in between the lines:
"For cloud datacenters, power consumption of HDDs is as important as their capacity. "
Helium makes things float, when the HDD gets lighter, the data center gets lighter. When the data center floats, where does it go? Into the clouds, BOOM! CLOUD data center!
@Yaldabaoth: "And have them fly into outer space?!"
The next evolution of storage. Good bye cloud storage. Time to store data in the cosmos. We can use moon storage as an interim solution and branch out from there.
You can't conduct heat through a vacuum. You can radiate heat (like light rays) accross a vacuum but that only covers the light/IR range and is much slower.
@tygrus: "You can't conduct heat through a vacuum."
True, but since this is only a vacuum chamber, you can just transfer heat via conduction through all the metal that eventually makes its way to the edges of the chamber where normal cooling methods take over. You may have to think out your conduction path a bit, but this is one of the lesser flaws of trying to design a "vacuum" HDD.
it's also not sold by amazon. it's a 3rd party selling through amazon marketplace, not the same thing. the more accurate way to write the story is that the drive is available on amazon, not sold by amazon.
Dang, I just pulled the trigger on 3x4TB Seagate ES drives. Cost me about $450, and in RAID5, it's 8TB usable. Only problem with a single drive is no failure protection, so you'd need two of them, and that would run almost $1400.00.
Too much $. When they come down into the $300 range they'll be well worth it.
Everyone always says that. I have a RAID5 5x2TB set which has had no problems in spite of a rebuild a few months into having the array (about 4-5 years ago). These are also WD Green drives, yet have had no problem except for the original first failure. Is it a critical array? Nope, just my media server. If I lost the whole thing it wouldn't be that big of a deal.
In a critical business setting, I'd be using RAID1 x2 (twin RAID1 mirrors sync'd daily).
Call me when the consumer/expansion 8TB and 10TB drives are available (and please, that ugly new checkerboard design for the expansion housings - get rid of it).
Just bought 2x$250 WD 'My Book 8TB' drives with HGST 7200 8TB drives. These drives rock, much faster, quieter, and cooler than the 4TB Seagates they replaced. He is the best thing that happened to HDD since PMR....
"Average Latency 4.16 ms" That's simply half a platter turn at 7200 rpm, so it applies to any 7.2k rpm drive (WD Gold) but says nothing about how quickly the heads move - which determines real world random performance, together with the firmware.
"... 243 or 254 MB/s maximum sustained transfer rate as well as 4.16 ms average latency, which is higher than the numbers listed by competing drives" Glad the latency is higher.. oh wait ;)
"idle noise of the He10: 20 - 36 dBA" No way it's such a huge span. 36 dBA is surely the rating under load.
"PowerChoice helps datacenter operators ... by ... even stopping disks completely, after an admin-defined interval of idle time" Wow, what huge amounts of energy could we have saved if we had implemented such a setting into the BIOS back in the 80's, and later on into the OS. Oh wait again.. :p
"PowerBalance technology helps the administrators to balance the power consumption and IOPS"
Curious what the settings are labeled? IOPS: Bad, IOPS: Worse?
It must be pretty degrading being a HDD engineer these days when all your market cares about is capacity and power. But I guess when a $40 Kingston SSD whips you by an order of magnitude you cant do much.
for a $700 harddisk why dont they just increase the cache up to 4G of cache ? we pay $20 only RETAIL PRICE for 4 G DDR4 today , and they still use 256 MB ONLY cache ? and demand 700$ for this drive ? it will only cost them 5$ more per drive ...
who cares about small chunks of data when the memory is dirt cheap today ? add those 4GB or even 8 GB of cache , and add capacitors to the drive in case of power loss to write that cache to the harddisk while the pc is offline . SIMPLE
Large cache sizes do not mean greater performance. The more cache you have the more files that can be stored in memory for pre-fetching. However, memory has to be pulled off the HDD and transferred into the cache, and in most cases the HDD itself is the bottleneck. 256 MB of cache is still quite a large amount, but performance differences get far smaller above sizes like that.
it does mean greater performance ! you just need to read it ONCE , and After that it will be in the cache Memory ... and all of us keep our pc in standby mode and never shut the pc off.
and keep in mind that The SSDHD exist with 8G of SSD caching and they work fine !
I didn't realize you were referring to an SSHD, as you describe. An SSHD is still not much faster. A disc drive is simply too much of a bottleneck for a flash cache (it rhymes!) storage to matter. A small OS SSD + a large storage HDD would be far faster.
You're far better off to put those 4 or 8 GB into your mainboard and use it as flexible system memory. It will be used as cache for all disks in the system, unless it's needed otherwise.
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ddriver - Thursday, April 28, 2016 - link
LOL, seagate doesn't dare offer more than 2 years on anything but "enterprise" grade. I wonder if they really have confidence in those products, or merely priced them twice as high as normal, so you are effectively buying two drives at once - the one you are gonna get right away and the one they will send for a replacement when it fails.takeshi7 - Monday, May 2, 2016 - link
I don't get your point. WD has a 2 year warranty on a lot of their products too.Alexvrb - Thursday, May 5, 2016 - link
If by "a lot of their products" you actually mean ONLY their entry-level bottom-line conventional Blue series, you're right. In their current lineup that's the only thing with a 2-year warranty. The Blue SSHD, standard Red, WD AV, and Purple series all carry a 3-year warranty. Their Red Pro, Black, and VelociRaptor series have a 5 year warranty. That's obviously not counting Enterprise-focused series which all carry a 5 year warranty except the Cold Storage Ae series which is still 3 years.Facts aside I might be biased because the majority of hard drive failures I've seen or dealt with have been Seagates, with the exception of a particular series of Deskstars which thankfully was not a mistake they repeated (later-gen designs after that were very solid). I also had great luck with Fujitsu, and was a bit sad to see them snatched up by Toshiba. So goes the shrinking HDD universe.
Donkey2008 - Saturday, May 7, 2016 - link
Ditto. I have RMA'd so many Seagate laptop drives that I don't even bother anymore and just replace them with Mushkin SSDs. Same goes for garbage Hynix memory modules. Dell fills their product line with these junk brands.takeshi7 - Wednesday, May 11, 2016 - link
The equivalent of the WD Red is the Seagate NAS HDD. It has a 3 year warranty.The equivalent of the WD Purple is the Seagate Surveillance HDD. It has a 3 year warranty.
The equivalent of the WD AV is the Seagate Video HDD. It has a 3 year warranty.
The equivalent of the WD Red Pro is the Seagate Enterprise NAS HDD. It has a 5 year warranty.
The only ones Seagate doesn't have an equivalent for that you listed is the WD VelociRaptor and the WD Black. On every other one of their products they have the same warranty as WD.
takeshi7 - Wednesday, May 11, 2016 - link
Oh, I just learned the equivalent to the WD Black is the Seagate Enterprise Capacity HDD. It has a 5 year warranty. Your argument is invalid.boeush - Thursday, April 28, 2016 - link
So... If they can manage to hermetically seal in Helium, why not go the extra mile and just hermetically seal a vacuum? Surely, platters/heads moving in near-total absence of any gases at all would require even less power? And it's not as if the task if maintaining a vacuum seal in the face of a single atmosphere's worth of external pressure is all that insurmountable: vacuum thermoses have been around for nearly a century -https://en.m.wikipedia.org/wiki/Vacuum_flask
CaedenV - Thursday, April 28, 2016 - link
Because the heads ride on a cushion of air that prevents them from crashing into the platter. If you had a vacuum then the slightest vibration would cause a head crash and destroy the drive.FunBunny2 - Thursday, April 28, 2016 - link
-- Because the heads ride on a cushion of air that prevents them from crashing into the platter.it's even more obvious: sealing HE in a case at atmospheric pressure is no big deal, while sealing a vacuum against atmospheric pressure certainly is.
HollyDOL - Friday, April 29, 2016 - link
Also, with vacuum you'd have to sustain constant outer pressure on the component at 100kPa... With vacuum you are getting to a completely different league in all steps - sealing, venting, cover pressure resistance, heads "gyroscope" thing you'd need to have and lots of other things I can't even think of :-)ShieTar - Friday, April 29, 2016 - link
"no big deal" is not entirely correct here, Helium is widely used as a measurement tool for leak rates, because it will leak faster and through smaller gaps than any other gas except for hydrogen. So to ensure a constant Helium pressure within a case (that may cycle in temperature quiet regularly) for 5 years is non-trivial.But yeah, still easier than vacuum. Which would lead to instant evaporation of normal lubricants as well, so you would have to replace the mechanism by something vacuum capable with a dry lubricant.
jabber - Saturday, April 30, 2016 - link
Actually maintaining a vacuum is easier than trapping helium long term.BurntMyBacon - Monday, May 2, 2016 - link
@jabber: "Actually maintaining a vacuum is easier than trapping helium long term."True. It is easier to keep an enclosure sealed against a nitrogen and oxygen leak than a helium leak, so maintaining a vacuum is easier than trapping helium long term. However, operating mechanical parts in a vacuum is not. The two big hitters that come to mind are how vibrations affect moving parts at small distances with no air cushion (think head crash) and how you keep joints and spindles from seizing up (liquid lubricants don't hold up in vacuum). I'm not sure dry lubricants are practical at normal HDD spindles speeds either.
FunBunny2 - Monday, May 2, 2016 - link
-- True. It is easier to keep an enclosure sealed against a nitrogen and oxygen leak than a helium leak, so maintaining a vacuum is easier than trapping helium long term.I'd like to see the equations on that, since this amounts to the assertion that He at standard temperature and pressure (at least, that's what current reporting states) inside a vessel will more easily escape a seal out of the vessel than atmosphere will breach a seal from outside a vacuum vessel (vessels engineered to contain/block passage).
ZeDestructor - Friday, June 3, 2016 - link
The helium goes straight through the metal because of how small the singl-atom molecules are (they fit between the atoms of the metal and go straight through..). Every other element has a bigger molecule in comparison and has a much harder time going through materials.boeush - Thursday, April 28, 2016 - link
I have trouble with that notion (of heads riding on a 'cushion' of air.) If anything, there are complexities of turbulence caused by friction, head movements, acoustic resonances - that would induce chaotic vibrations to begin with. And if Bernoulli physics have not yet been repealed, I'd expect the air near the platter to be moving faster (due to platter-air friction tugging it along) than air at the midpoint between platters - and faster moving air means lower pressure. Which would imply that the air dynamics would actually act to pull the heads toward the platter rather than 'floating' them - so the heads would have to incorporate some kind of an airfoil-like wing just to counter that force. Which introduced yet more friction and turbulence losses/instabilities into the system.Azethoth - Thursday, April 28, 2016 - link
I have trouble with people posting giant paragraphs about how they don't understand engineering or physics and doubting the factual statements made by more knowledgeable posters.Try to be scientific and curious. Instead of spouting all this pseudo science (are you trying to convince us you are smart?), just go google it. You will quickly learn that drive heads ride on a cushion of air as stated. In the face of actual facts go reread your post and be humble and curious next time.
This may sound harsh to you, but it will help you in your job and life if you have a curious "I want to learn" attitude.
Anato - Friday, April 29, 2016 - link
+1Hard drives are just like Boeush described they couldn't be.
saratoga4 - Friday, April 29, 2016 - link
This is a great post.cyberguyz - Friday, April 29, 2016 - link
I seriously roflmao'ed at that post.Air cushioning of the heads have been a known fact for as long as winchester-based DASD has existed.
What do they teach kids in school these days?
FunBunny2 - Friday, April 29, 2016 - link
-- Air cushioning of the heads have been a known fact for as long as winchester-based DASD has existed.longer actually. IIRC, the first DASD from IBM mainframes exploited "floating heads", at least the 1301 drive. that was 1961:
"The 1301 is the first disk drive to use heads that are aerodynamically designed to fly over the surface of the disk on a thin layer of air."
here: https://en.wikipedia.org/wiki/History_of_IBM_magne...
Kalessian - Friday, April 29, 2016 - link
I personally don't think the things he said warranted this kind of attitudedueckadam - Saturday, April 30, 2016 - link
I really don't see what he's doing so wrong. He has some knowledge that makes him think one thing, and he's presented with information that conflicts with that, and he's trying to reconcile the two. Really, the conclusions he's drawing do seem reasonable, even if they're incorrect.As far as googling it, it's not as easy as it sounds. Sure, it's easy to find stuff saying that the head rides on a cushion of air, but I wasn't able to find much explaining the phenomenon, i.e. the mechanism by which the air bearing forms or how it acts as a cushion. So if you're as knowledgeable about engineering and physics as the condescending tone of your post implies, would you care to try and explain, or provide a source that does?
Solandri - Monday, May 2, 2016 - link
He's not spouting pseudo-science. What he's describing is exactly what happens with an incompressible fluid like water. It's why ships need tugboats to push them away from docks - they can't do it under their own power (unless they have a bow thruster), since any forward or backwards movement just pushes them closer to the dock. The QE2 ran aground partly due to this effect (high speed over shallow water caused it to be "sucked" down by Bernoulli forces).https://en.wikipedia.org/wiki/Squat_effect
Air (and helium) however are compressible, which leads to a different phenomenon (ground effect) which counters Bernoulli.
sor - Thursday, April 28, 2016 - link
You forget what would be causing the gas to move at all:the platter. The gas is actually caught by the platter as it spins, sucking it under the heads.If you lay a piece of paper on a table, lift one side, and try to blow under it, it won't magically stick harder to the table. Yes, there is air moving, but you can't overcome displacement. The pressure is actually higher as it is being compressed/forced, and the movement is alleviating the pressure.
sor - Thursday, April 28, 2016 - link
Sucking is probably a bad way to describe it... The platter actually pushes the air it contacts, which increases pressure under the heads and creates the cushion.BurntMyBacon - Monday, May 2, 2016 - link
@sor: "The platter actually pushes the air it contacts, which increases pressure under the heads and creates the cushion."Which is possible because air/helium is compressible. In fact, it is this compressibility that stabilizes the heads. It makes it act as a shock absorber of sorts.
@Solandri: " What he's describing is exactly what happens with an incompressible fluid like water. ... Air (and helium) however are compressible, which leads to a different phenomenon (ground effect) which counters Bernoulli."
This. The Bernoulli effect doesn't disappear, it simply ceases to be the dominant force. Interestingly, IIRC, it actually helps dampen vibrations by resisting the repulsing part of the vibration.
MrSpadge - Friday, April 29, 2016 - link
As far as I know you're correct - the only piece missing is that the heads are indeed aerodynamically designed to provide the proper force repelling them from the platter. That's what Azethoth described in fancy scientific language ("riding the cushion of air").freeskier93 - Saturday, April 30, 2016 - link
Your critical flaw is the misguided use of Bernoulli's principal. Bernoulli's principal is actually derived from Navier-Stokes through certain assumptions, which are not applicable here. What we're actually looking at in the case of spinning platters is a Couette flow, where a velocity is created through shear forces in the fluid and NOT a pressure gradient. There is no pressure gradient in the tangential direction.Solandri - Monday, May 2, 2016 - link
That's a pretty good recollection of physics - just enough to get you into trouble. What you're describing happens if the fluid is a liquid. We ran into it all the time with our robot submersibles - if you get too close while running parallel to a wall, the submersible gets "sucked" against it by Bernoulli forces and you're stuck (need to turn so a thruster can push you away... if you have enough room to turn).It's different when the fluid is a gas. At moderate distances, Bernoulli rules. But as the two surfaces get very close, the compression of the gas as it squeezes between the head and platter overpowers Bernoulli, and you get a high pressure zone. In aircraft, it's called ground effect, and can be used to greatly extend cruising range because the higher pressure between the wing and ground (or water) creates more lift, reducing drag.
surfnaround - Friday, May 13, 2016 - link
@boush ...Read up on dunning-kruger effect... boeush!
One problem that you have not realized ... The cushion is caused by the platter spinning... Not by the drive head spinning...
Your understanding of physics is limited to airplane wings, because what your have described is an airplane wing moving through air...
boeush - Thursday, April 28, 2016 - link
P.S. If I had a goal of preventing read/write heads from crashing into platters in a vacuum enclosure, I might look into giving both the heads and the platters a matched electrostatic charge (i.e. both positive, or both negative) so that they repel each other - and do so more strongly the closer they get. Only issue would be calibrating the charge strength against the magnetic field induced by charges in relative motion and the resistivity of the storage medium (so the stored data doesn't get mangled by the mere act of spinning the platter past the moving head.)Azethoth - Thursday, April 28, 2016 - link
You are totally dazzling me with your HDD building prowess. Is there a twitter feed I can subscribe to? Are you going to start your own vacuum HDD company with auto erase as you read and write technology? Can I get shares now?LeftSide - Friday, April 29, 2016 - link
This is quite possible the dumbest thing, or most amusing thing I've read all week. All depending on whether you're trolling or not.frostyfiredude - Friday, April 29, 2016 - link
Ah brilliant, that would just recreate the original problem again, put some force on the disk in a lopsided manner then spin it. This time by using charges that conveniently erase disk sectors as the disk rotates. How many RPM will it take before that disk wobbles out of control or tears itself apart I wonder.TheinsanegamerN - Friday, April 29, 2016 - link
So, your HDD would constantly wipe itself. Fantastic job. What next, a car that has no wheels?web2dot0 - Thursday, April 28, 2016 - link
You really think the engineers working for the company are that dense as not have thought about that? The hard drive industry have been around of decades. I think they know a thing or two about the intricacies of building a hard drive by now ....webdoctors - Thursday, April 28, 2016 - link
A vacuum isn't the same as Helium. Its more than just the reduced drag of using Helium. Read in between the lines:"For cloud datacenters, power consumption of HDDs is as important as their capacity. "
Helium makes things float, when the HDD gets lighter, the data center gets lighter. When the data center floats, where does it go? Into the clouds, BOOM! CLOUD data center!
Death666Angel - Thursday, April 28, 2016 - link
Made my day!Gigaplex - Thursday, April 28, 2016 - link
Helium is lighter than air, but is much heavier than a vacuum. A vacuum sealed drive would float better.Yaldabaoth - Thursday, April 28, 2016 - link
And have them fly into outer space?!TheinsanegamerN - Friday, April 29, 2016 - link
There is way more room in space. We could triple the size of the cloud for no extra cost!BurntMyBacon - Monday, May 2, 2016 - link
@Yaldabaoth: "And have them fly into outer space?!"The next evolution of storage. Good bye cloud storage. Time to store data in the cosmos. We can use moon storage as an interim solution and branch out from there.
Azethoth - Thursday, April 28, 2016 - link
Dude, did you just invent the unobtanium from Avatar?AndrewJacksonZA - Friday, April 29, 2016 - link
Haha! Well done webdoctors, you win 10 000 internet points! :-)Eden-K121D - Friday, April 29, 2016 - link
Awesome. Your Data in the Clouds. AnandTech Should Hvae Upvote Systemtygrus - Friday, April 29, 2016 - link
You can't conduct heat through a vacuum. You can radiate heat (like light rays) accross a vacuum but that only covers the light/IR range and is much slower.BurntMyBacon - Monday, May 2, 2016 - link
@tygrus: "You can't conduct heat through a vacuum."True, but since this is only a vacuum chamber, you can just transfer heat via conduction through all the metal that eventually makes its way to the edges of the chamber where normal cooling methods take over. You may have to think out your conduction path a bit, but this is one of the lesser flaws of trying to design a "vacuum" HDD.
coburn_c - Thursday, April 28, 2016 - link
That 'On Amazon' link says tomshardware.com. Also it doesn't work.Ryan Smith - Thursday, April 28, 2016 - link
Fixed.cygnus1 - Thursday, April 28, 2016 - link
it's also not sold by amazon. it's a 3rd party selling through amazon marketplace, not the same thing. the more accurate way to write the story is that the drive is available on amazon, not sold by amazon.bill.rookard - Thursday, April 28, 2016 - link
Dang, I just pulled the trigger on 3x4TB Seagate ES drives. Cost me about $450, and in RAID5, it's 8TB usable. Only problem with a single drive is no failure protection, so you'd need two of them, and that would run almost $1400.00.Too much $. When they come down into the $300 range they'll be well worth it.
beginner99 - Friday, April 29, 2016 - link
RAID5 with 4 TB drives isn't really a good idea however. Changes the rebuild will fail as well are pretty huge.bill.rookard - Friday, April 29, 2016 - link
Everyone always says that. I have a RAID5 5x2TB set which has had no problems in spite of a rebuild a few months into having the array (about 4-5 years ago). These are also WD Green drives, yet have had no problem except for the original first failure. Is it a critical array? Nope, just my media server. If I lost the whole thing it wouldn't be that big of a deal.In a critical business setting, I'd be using RAID1 x2 (twin RAID1 mirrors sync'd daily).
darkfalz - Thursday, April 28, 2016 - link
Call me when the consumer/expansion 8TB and 10TB drives are available (and please, that ugly new checkerboard design for the expansion housings - get rid of it).Michael Bay - Friday, April 29, 2016 - link
Consumer 8Tb is available right now. I`ve got one, aiming for one more.Pneumothorax - Friday, April 29, 2016 - link
Just bought 2x$250 WD 'My Book 8TB' drives with HGST 7200 8TB drives. These drives rock, much faster, quieter, and cooler than the 4TB Seagates they replaced.He is the best thing that happened to HDD since PMR....
MrSpadge - Friday, April 29, 2016 - link
"Average Latency 4.16 ms"That's simply half a platter turn at 7200 rpm, so it applies to any 7.2k rpm drive (WD Gold) but says nothing about how quickly the heads move - which determines real world random performance, together with the firmware.
"... 243 or 254 MB/s maximum sustained transfer rate as well as 4.16 ms average latency, which is higher than the numbers listed by competing drives"
Glad the latency is higher.. oh wait ;)
"idle noise of the He10: 20 - 36 dBA"
No way it's such a huge span. 36 dBA is surely the rating under load.
"PowerChoice helps datacenter operators ... by ... even stopping disks completely, after an admin-defined interval of idle time"
Wow, what huge amounts of energy could we have saved if we had implemented such a setting into the BIOS back in the 80's, and later on into the OS. Oh wait again.. :p
Gunbuster - Friday, April 29, 2016 - link
"PowerBalance technology helps the administrators to balance the power consumption and IOPS"Curious what the settings are labeled? IOPS: Bad, IOPS: Worse?
It must be pretty degrading being a HDD engineer these days when all your market cares about is capacity and power. But I guess when a $40 Kingston SSD whips you by an order of magnitude you cant do much.
samer1970 - Saturday, April 30, 2016 - link
I dont get it ,for a $700 harddisk why dont they just increase the cache up to 4G of cache ? we pay $20 only RETAIL PRICE for 4 G DDR4 today , and they still use 256 MB ONLY cache ? and demand 700$ for this drive ? it will only cost them 5$ more per drive ...
who cares about small chunks of data when the memory is dirt cheap today ? add those 4GB or even 8 GB of cache , and add capacitors to the drive in case of power loss to write that cache to the harddisk while the pc is offline . SIMPLE
negusp - Sunday, May 1, 2016 - link
Large cache sizes do not mean greater performance. The more cache you have the more files that can be stored in memory for pre-fetching. However, memory has to be pulled off the HDD and transferred into the cache, and in most cases the HDD itself is the bottleneck. 256 MB of cache is still quite a large amount, but performance differences get far smaller above sizes like that.samer1970 - Monday, May 2, 2016 - link
it does mean greater performance ! you just need to read it ONCE , and After that it will be in the cache Memory ... and all of us keep our pc in standby mode and never shut the pc off.and keep in mind that The SSDHD exist with 8G of SSD caching and they work fine !
negusp - Monday, May 2, 2016 - link
I didn't realize you were referring to an SSHD, as you describe. An SSHD is still not much faster. A disc drive is simply too much of a bottleneck for a flash cache (it rhymes!) storage to matter. A small OS SSD + a large storage HDD would be far faster.MrSpadge - Monday, May 2, 2016 - link
You're far better off to put those 4 or 8 GB into your mainboard and use it as flexible system memory. It will be used as cache for all disks in the system, unless it's needed otherwise.tygrus - Monday, May 2, 2016 - link
So they have inflated the hype with everybody getting overly excited and speaking in higher pitched voices. LOL