Are disk bearings really harmed by spin-up?

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage,alt.video.ptv.tivo (More info?)

"zaw" <zaw@verizon.net> wrote:
> HDD are better when they're running and they're mounted Horizontally.
> That's where everything is perfect.

Reps at various HDD manufacturers say that orientation doesn't matter.


Rick Lowen

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage,alt.video.ptv.tivo (More info?)

"Richard Lowen" <LowensDen@HeissMail.com> wrote in message
news:bs-dnd7HCIrkNhvfRVn-pw@comcast.com...
>
> What you and almost everyone else ignores is the energy used to
> mine the raw materials and the energy to manufacure the components
> and the energy to assemble those components into products. Add to
> that the energy to get the workers to the manufacturing site, etc., and
> it could very well be that more energy is used to make a product than
> to operate it. So what you could have is a big energy WASTE if you
> don't prolong the life of your products by minimizing the number of
> power on/off cycles. In short, it's the overall cost in energy that
counts,
> not just the energy of operation.
>
Nonsense.

The energy to run a 100W computer for 5 years is 5*365*24*0.1 = 4380 kWh, or
$200-400. That exceeds the cost of entry level computers. Energy to
manufacture it is only a portion of that.

 

[peter]

Archived from groups: comp.sys.ibm.pc.hardware.storage,alt.video.ptv.tivo (More info?)

> Reps at various HDD manufacturers say that orientation doesn't matter.

Actually that is not true. They restrict hard drive position to
a few orientations.

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage,alt.video.ptv.tivo (More info?)

Richard Lowen wrote:
> "zaw" <zaw@verizon.net> wrote:
>
>> HDD are better when they're running and they're mounted Horizontally.
>> That's where everything is perfect.
>
> Reps at various HDD manufacturers say that orientation doesn't matter.

I've heard that it is OK to run disks horizontal, vertical, or upside
down, but not diagonally. An older Dell PC I worked on yesterday has
one disk vertical at the front of the tower and the other disk upside
down under the floppy drive. Any orthogonal orientation is OK.
-Joe

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage,alt.video.ptv.tivo (More info?)

"Jack Tyler" <jctyler_67@yahoo.com> wrote in message news:1116082584.736454.303860@o13g2000cwo.googlegroups.com
> Howard wrote:
>
> > > If anyone has thorough technical articles on hard drive wear, please
> > > post. Specifically, what is so torturous about spinning up the drive,
> > > and how can that brief cycle be quantified, damage-wise against
> > > constant spinning with higher heat levels?
> >
> > You posted from google groups...so what did the archive say about the past
> > discussions on this topic?
>
> Lots of hearsay in past discussions. This thread has been a lot more
> informative.

Strange how more hearsay suddenly turns into information as soon as the
question is asked by poster as an originator rather than him being a lurker.

>
> JT

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage,alt.video.ptv.tivo (More info?)

"Eric Gisin" <ericgisin@hotmail.com> wrote:..
> "Richard Lowen" <LowensDen@HeissMail.com> wrote:
>>
>> What you and almost everyone else ignores is the energy used to
>> mine the raw materials and the energy to manufacure the components
>> and the energy to assemble those components into products. Add to
>> that the energy to get the workers to the manufacturing site, etc., and
>> it could very well be that more energy is used to make a product than
>> to operate it. So what you could have is a big energy WASTE if you
>> don't prolong the life of your products by minimizing the number of
>> power on/off cycles. In short, it's the overall cost in energy that
>>counts, not just the energy of operation.
>>
> Nonsense.
>
> The energy to run a 100W computer for 5 years is 5*365*24*0.1 =
> 4380 kWh, or $200-400. That exceeds the cost of entry level computers.
> Energy to manufacture it is only a portion of that.


That's assuming you would run the computer 24/7. But if the question
is whether to turn it off every 1/4 hr for 1/4 of an hour AND turn it off for
12 hours (as most people do), the energy savings is only $25-$50, and
the life of the computer might be cut in half by the frequent power cycling.


Rick Lowen

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage,alt.video.ptv.tivo (More info?)

Jack Tyler <jctyler_67@yahoo.com> wrote in message
news:1116082772.171080.158900@f14g2000cwb.googlegroups.com...
> Rod Speed wrote

>> There's a reason for the number of start stop
>> cycles specified in the hard drive datasheets.

> I think I need to find and read those datasheets.
> If you have any quick links, please post.

http://www.hgst.com/hdd/support/table3.htm
Generally in the Technical Library documentation link for each drive.
One specific example is
http://www.hitachigst.com/tech/techlib.nsf/techdocs/E8C3F8F6F3819BDB86256CE9005AB0B9/$file/d7k250P_sp.pdf

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage,alt.video.ptv.tivo (More info?)

Jack Tyler <jctyler_67@yahoo.com> wrote in message
news:1116083555.966977.39450@g14g2000cwa.googlegroups.com...
> Rod Speed wrote:

>> The start stop cycles specified in the hard drive datasheets
>> are the most imporant numbers. They can be exceeded by
>> a startup every hour surprisingly quickly.

> http://www.pcguide.com/ref/hdd/perf/qual/specCycles-c.html

> Well, I'm reading that start/stop cycles > are typically
> in the 30k to 50k range, and that's something I didn't
> know. I wasn't looking for the right keywords.

Yeah, thats the main problem.

> One boot per day on a home PC would
> allow for 109 years at 40k cycles,

But only a couple of years if you set it to power down on 30
mins of inactivity and it gets used at something like that rate,
say to poll for new email and dont turn it off overnight.

> which means other components must wear out faster than bearings!

Yes, bearing failure isnt seen much anymore with desktop hard drives.

Tho we havent been using fluid bearings
for all that long, so that may change too.

> This is the info I needed.

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage,alt.video.ptv.tivo (More info?)

Jack Tyler <jctyler_67@yahoo.com> wrote in message
news:1116085334.241353.283510@g44g2000cwa.googlegroups.com...
> Rod Speed wrote

>>> Would anyone claim that car wheel bearings get as much wear
>>> when you pull out of the driveway vs. a 500 mile nonstop trip?

>> Completely different to hard drives.

> In principle it's the same,

Nope, nothing like it. The bearings are completely different,
you dont get anything like the spinup torque you get on a
hard drive platter with a car wheel, and the hard drive has
a single bearing on one end of the axle too.

> just with a lot more load on those wheel bearings.

Much bigger bearings.

> They take a lot of stress when you drive

The main stress on the bearings with car wheels
is when you drop into a pothole at speed etc.

> so I question that pulling out of the garage is
> significantly worse than a long trip on a hot day.

Nope.

> Cold engine starts are different because oil has to be pulled
> up farther from the crankcase, though there's usually film left
> on the cylinder walls and crank bearings. Slick 50's claims
> of metal on metal are overhyped. But this is getting off topic.

And completely different to a hard drive bearing anyway.

>>> Why does Windows have a "Turn off hard disks"
>>> feature in Power options if not to reduce bearing wear?

>> To reduce power used, just like with monitors and motherboards.

> Other posters have claimed that power usage is nil but clearly it's not.

Its in all the datasheets. 5W is pretty typical for a modern IDE drive.

> My main angle on this was about saving energy. Multiply 5 watts
> by millions of computers and you've saved a lot of power.

Still a fart in the bath in total power consumption.

> Do that with countless other gadgets and you've saved a lot more.

Still a fart in the bath in total power consumption.

> People leave work monitors on all weekend (with
> goldfish tank displays) when they're gone. Too much
> trouble to push the off button or let the screen blank out?

Hardly the end of civilisation as we know it any time soon.

> Diesel owners idle their engines way too much, etc..

> Anything that doesn't have to run 24/7 could be turned off

No thanks, I turn hardly anything off.

> instead of blaming it all on Kenneth Lay and the Arabs.

Wouldnt fix the problem even if they did
turn everything off that didnt need to be on.

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage,alt.video.ptv.tivo (More info?)

Jack Tyler wrote:

> Rod Speed wrote:
>
>> > Would anyone claim that car wheel bearings get as much wear
>> > when you pull out of the driveway vs. a 500 mile nonstop trip?
>>
>> Completely different to hard drives.
>
> In principle it's the same, just with a lot more load on those wheel
> bearings. They take a lot of stress when you drive so I question that
> pulling out of the garage is significantly worse than a long trip on a
> hot day. Cold engine starts are different because oil has to be pulled
> up farther from the crankcase, though there's usually film left on the
> cylinder walls and crank bearings. Slick 50's claims of metal on metal
> are overhyped. But this is getting off topic.
>
>> > Why does Windows have a "Turn off hard disks"
>> > feature in Power options if not to reduce bearing wear?
>>
>> To reduce power used, just like with monitors and motherboards.
>
> Other posters have claimed that power usage is nil but clearly it's
> not. My main angle on this was about saving energy. Multiply 5 watts by
> millions of computers and you've saved a lot of power. Do that with
> countless other gadgets and you've saved a lot more. People leave work
> monitors on all weekend (with goldfish tank displays) when they're
> gone. Too much trouble to push the off button or let the screen blank
> out? Diesel owners idle their engines way too much, etc..
>
> Anything that doesn't have to run 24/7 could be turned off instead of
> blaming it all on Kenneth Lay and the Arabs.

You wanna see _waste_, go outside tonight and look up. And every single one
of those is blasting enough power into space in a single second to run all
of human civilization at its current level for about a million years.
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage,alt.video.ptv.tivo (More info?)

In comp.sys.ibm.pc.hardware.storage Randy S. <rswittNO@spamgmail.com> wrote:
[...]
>> There is one component that is put under very high stress at start-up,
>> especially in a server with many disks: The Power Supply Unit. PSUs
>> regularly fail on start-up and far less often during normal
>> operation. That is one of several reasons why servers are usually
>> running 24/7, even if they are not needed all the time. But take note
>> that in Servers HDDs are usually cooled well.

> Also, well designed servers will do a "staggered" start, i.e. they won't
> start all of the hard drives at once, but at intervals, like 1 every 2
> seconds. HDD startup takes a *lot* of juice, and if you have 5 or 6 or
> more HDD's in a system you either have to *way* oversize your power
> supply to handle the startup load, or more cheaply, stagger the start so
> a smaller power supply can handle it. A staggered start can slow bootup
> a *lot*, so it really discourages cold booting a server.

Indeed. That is possibly an other factor.

Personally in my PC servers I go for PSUs that can take the full
spin-up load of all disks at once. That has the advantage that during
normal operation the PSU is not under higher load, which should
increase its lifetime. The limit for this is somewhere around 10-15
disks, since PSUs with more than 550W are dificult to get.

Arno

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage,alt.video.ptv.tivo (More info?)

> Indeed. That is possibly an other factor.
>
> Personally in my PC servers I go for PSUs that can take the full
> spin-up load of all disks at once. That has the advantage that during
> normal operation the PSU is not under higher load, which should
> increase its lifetime. The limit for this is somewhere around 10-15
> disks, since PSUs with more than 550W are dificult to get.

Most client PC's don't have any need for staggered spin-up, so I'd
totally agree with you. It's only in good size servers with lots of
RAIDed drives that it's really an issue.

Randy S.

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage,alt.video.ptv.tivo (More info?)

"Rod Speed" <rod_speed@yahoo.com> wrote in message news:3en11fF3uk2bU1@individual.net
> Jack Tyler <jctyler_67@yahoo.com> wrote in message news:1116085334.241353.283510@g44g2000cwa.googlegroups.com...
> > Rod Speed wrote
>
> > > > Would anyone claim that car wheel bearings get as much wear
> > > > when you pull out of the driveway vs. a 500 mile nonstop trip?
>
> > > Completely different to hard drives.
>
> > In principle it's the same,
>
> Nope, nothing like it. The bearings are completely different,
> you dont get anything like the spinup torque you get on a
> hard drive platter with a car wheel, and the hard drive has

> a single bearing on one end of the axle too.

Nonsense.

[snip]

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage,alt.video.ptv.tivo (More info?)

Considering that the HDD's bearing must be very tight (probably with
sub-micron play), in what ways do you think such tightness affects the
bearing's operation during startup and in steady mode?

"Randy S." <rswittNO@SPAMgmail.com> wrote in message
news:d625ta$18f6$1@spnode25.nerdc.ufl.edu...
>
> Careful, you're showing your inexperience. If you are really asking the
> question, don't draw incorrect conclusions from assuming an answer.
> Startup wear is large for four reasons:
>

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage,alt.video.ptv.tivo (More info?)

Alexander Grigoriev wrote:
> Considering that the HDD's bearing must be very tight (probably with
> sub-micron play), in what ways do you think such tightness affects the
> bearing's operation during startup and in steady mode?
>

I was being very general. Fit tolerences had large effects in bearings
that I used to design because often the inner race, outer race, and
bearing elements were all manufactured from different alloys (usually
titanium alloys, steel alloys and sometimes nickel or aluminum alloys).
The thermal coefficient (alpha) of these materials varied enough that
fit tolerences would change significantly as temperature changed.
You're correct that the fits are fairly tight (though *far* from
sub-micron, I think you're thinking of the bearing and race finishes,
which must be that close. Submicron fits wouldn't allow room for
lubrication movement, or even movement at all!), which *exacerbates*
thermal effects.

With HDD bearings, the inner and outer races are almost certainly the
same material, so thermal changes wouldn't change their fits, though the
bearing elements probably have some variation. Also, I was typically
working with thermal changes of 500 deg. F and up, HDD's only see a
delta of 100 degrees or so, so that would make it less significant.

Randy S.

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage,alt.video.ptv.tivo (More info?)

FWIW, the startup current causes a lot of stress in the drive
electronics too, especially the power circuitry and motor drivers. I
remember electrolytic caps blowing when you power cycled certain drives
too often. That may be less of an issue today than in the good old days
of many-platter 8" and 5.25" drives, but the electronics got smaller
too so it definitely gets stressed. Also, unless you have ramp loading
(which has its own set of issues), the heads get thermally stressed
through friction, in addition to the mechanical stress.
I leave my drives on 24*7.

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage,alt.video.ptv.tivo (More info?)

(Jason) wrote in alt.video.ptv.tivo:
> I hope they never put in such an option, because there have been
> plenty of times that 30 minute buffer has been astoundingly
> useful. For example, a few days ago when that 2-seater cessna
> flew over washington d.c. I walked into the room and saw people
> running down the street. 'What the hell?', I think; and rewinding
> 10 minutes gives the story.

That's why I want TiVo for real life. I could have seen it live if I would
have been able to back up 30 minutes and go outside.

--
Jeff Rife | "You keep using that word. I do not think it
| means what you think it means."
|
| -- Inigo Montoya, "The Princess Bride"

 

[Howard]

Archived from groups: comp.sys.ibm.pc.hardware.storage,alt.video.ptv.tivo (More info?)

"Randy S." <rswittNO@SPAMgmail.com> wrote in news:d6ajh0$u82$1
@spnode25.nerdc.ufl.edu:

> Well, I like the live buffer too, plus, as I think we've already reached
> a consensus on, the significance of full time operation of the HDD in a
> Tivo is probably close to nil.

I don't know if I would say that. The 'it's wasting energy!' people would
(and will...most likely within a week at the rate they have been going
lately) say it is a very high significance. They keep desperately reaching
for some other, more valid excuse though, and try to say you are doing no
harm by turning the device off. As we've all seen (many many times over
now, it surely is getting old) this not only keeps you from using the
device as it is intended, you ARE, in fact, doing harm.

Someday, they'll get a clue that it's not a 'waste' when I'm using the
energy IN THE EXACT WAY I WANT TO.

Ok, no they won't, but I can dream.

--
Minister of All Things Digital & Electronic, and Holder of Past Knowledge
stile99@email.com. Cabal# 24601-fnord | Sleep is irrelevant.
I speak for no one but myself, and |Caffeine will be assimilated.
no one else speaks for me. O- | Decaf is futile.

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage,alt.video.ptv.tivo (More info?)

Howard wrote:
> "Randy S." <rswittNO@SPAMgmail.com> wrote in news:d6ajh0$u82$1
> @spnode25.nerdc.ufl.edu:
>
>
>>Well, I like the live buffer too, plus, as I think we've already reached
>>a consensus on, the significance of full time operation of the HDD in a
>>Tivo is probably close to nil.
>
>
> I don't know if I would say that. The 'it's wasting energy!' people would
> (and will...most likely within a week at the rate they have been going
> lately) say it is a very high significance. They keep desperately reaching
> for some other, more valid excuse though, and try to say you are doing no
> harm by turning the device off. As we've all seen (many many times over
> now, it surely is getting old) this not only keeps you from using the
> device as it is intended, you ARE, in fact, doing harm.

Sorry, you're right, I meant to say that it as little significance to
the *reliability* of the device. Power savings are a different matter.
I wasn't precise enough ;-)

Randy S.