Planned Obselescence....A Good Thing?
clare at snyder.on.ca wrote
Rod Speed wrote
clare at snyder.on.ca wrote
Rod Speed wrote
lsmartino wrote
Rod Speed wrote
Please explain how the manufacturer of a light bulb, fluorescent
lamp or CFL can provide an estimate of the lifetime of the lamp.
That is trivial to do by running an adequate sized batch of
incandescent light bulbs under appropriate test conditions etc.
Donīt say "They canīt because itīs impossible".
Explain exactly why itīs impossible.
Its up to those who claim that its possible to design a device
to die one year after the warrant expires how that can be done.
Well, it can be estimated how long will a power semiconductor
run if you leave it without a proper heatsink.
Not in a domestic environment it aint, because
the ambient temperature varys so much.
I got a bit of a start relatively recently when someone was having
overheating problems with their PC to discover that they were one
of the few in this area who were silly enough to have no form of
cooling whatever, not even a swamp cooler, in an area which can
see 10 days over 40C some summers. We had one just last week
and it got to 44C, and it was like walking into a furnace walking
outside my airconditioned house.
Open any Samsung TV, for instance, to see for yourself
how important transistors are left bare, dissipatting heat
to the air. I donīt see why it should be difficult for the
manufacturer to know that these particular transistors
left overheating will fail within a finite number of hours.
There is no finite number of hours, because the
ambient temp varys so much in domestic situations.
Those who dont have any cooling at all in an area which
can see a week over 40C wont survive the warranty
period and those who have decent air conditioning will
find that the TV lasts long past the warranty period.
Also, you will notice that the same circuit will have electrolytic
capacitors near heat sources, when itīs a well known fact that
heat shortens dramatically the life of electrolytics caps.
In practice that isnt a significant problem with domestic
appliances. Essentially because you dont see many electros in that
situation with them.
The manufacturer know how to properly design an electronic
circuit in order to provide a long life, but it also it knows how
to design it to fail within a short term under certain conditions,
No they dont on that silly claim about surviving the
warranty fine, but failing immediately after that expires.
and accordingly they estimate a warranty just long
enough to cover the product for a safe term, a
safe term for the manufacturer, not the user.
Have fun explaining how come not a single electronic device
I have ever owned has died just after the warranty has run out.
And that includes my latest gigantic widescreen TV too.
Of course itīs impossible to predict exactly how many years
the TV will last, but the manufacturer count with statistical
data which says, for instance, that a TV set is turned on
10 hours per day for instance, and taking that into account,
and estimating how long the weakest part of the TV will last
under these conditions, they can determine the warranty lapse.
Pity about the TVs that get left on all the time.
The claim is completely fanciful and those making that sort of
claim have obviously never actually designed a damned thing.
And only the stupidest manufacturer would deliberatly design
their product to die as soon as the warranty has expired
anyway, because the bulk of those who had bought such
a dud wouldnt be buying another from that manufacturer.
They also do product reliability testing to see
how long on average it is before a product fails.
No they dont with domestic appliances.
They dont even do that with mass market hard drives anymore.
Yes they do.
No they dont.
They quote the useful lifetime of a hardrive in MTBF hours.
That is calculated, not measured. Convert that MTBF
to years and you will discover why they cant possibility
have tested them to get those numbers.
Donīt answer "itīs impossible" if you are not prepared to give
a real explanation. Samsung, Seagate, WD... any decent hard
drive manufactures gives an estimate lifetime of their products.
These estimates are provided in the datasheet of each harddrive.
And they are ESTIMATES, not measured results.
Exactly, these are estimates,
Pity the claim was about TESTING, which doesnt happen, like I said.
and most of the time very accurate,
Like hell it is. Have you actually tried converting
the MTBF of a current hard drive to years ?
The average quality EIDE drive has a published MTBF of
400,000 hours. That wouild be 45 years on my computer.
Yep, that's what I meant.
I've had LOTS that never made 3 years.
You arent cooling them properly.
BS. They have NEVER gone over 40 degrees C. They live year round
between 65 and 72 degrees F (talking about my own systems)
Then there is some other problem with the system
they are used in, most likely the power supply.
They start losing sectors after about a year, and
reach the undependable stage after 2 or three.
Have fun explaining how come others dont get that effect with those drives.
Some last 2 years, and some are still going after 7.
I've even got a Fujitsu MPG still running, and doing just
fine (that's one out of well over 100 I put into service)
If they test 1000 drives for 400 hours and get one failure, they
have their MTBF of 400,000 hours - 1 failure in 400,000 hours of
running.
Nope, it aint measured like that.
They will actually do a larger test sample over
a larger time span Likely 2500 for 500 hours.
No they dont with mass market commodity drives.
Give it up.
No thanks. That isnt done with mass market commodity drives.
That gives them 125,000,000 running hours and if they
have 3.125 failures they have a 400,000 hour MTBF.-
They dont determine the MTBF like that either.
but that's how the numbers are arrived at if they are not just
using statistical analysis methods.(predictive failure). Today's
hard drives with S.M.A.R.T. technology can predict their
failure date quite accurately. (using third party software).
Nope, they cant even consider the majority
of drives that fail with no prior indication of failure.
Other than bearing failure (which CAN cause S.M.A.R.T.
to find anomolies) and drive electronics failures,(which
generally do not, as they fail "hard") they can and DO
predict failure before any "prior indication of failure"
Pity about the drive electronics failure which doesnt and
which is now the most significant drive failure mode as
long as the drive isnt abused temperature wise or power.
I just pulled 2 drives from service because they
predicted their own death in less than 60 days.
Bet they wouldnt have failed in that time.
My time to restore the sytem is worth more than the replacement
drive, so I replace when it says there is a problem. Tried stretching
a laptop drive that said there was a problem developing and had to
replace it and do a complete restore less than 2 weeks later.
Plenty have found that steaming turd got the prediction completely wrong
and it was obvious why it was getting it wrong from the raw smart data too.
AND the smart data isnt necessarily an indication of an imminent
drive failure anyway, it can be due to factors outside the drive itself.
That steaming turd gets it wrong much more often than it gets it right.
One was made on the 123rd day of 2003 (seagate),
the other the last day of January 2004 (wd).
Being a WD Caviar retail drive it has a 1 year warranty. If it
was a "distribution" drive, it would have a 3 year warranty.
Might have lasted 2 years - but I don't take a chance on my data.
Anyone with a clue has proper backups.
Yup - have backups of all the data.
So your
Might have lasted 2 years - but I don't take a chance on my data.
is completely silly.
Still have to re-install all the OS and programs,
along with the myriad updates and patches.
No you dont if you do backups properly.
Also, when is the last time you actually TESTED your backup?
I do it all the time, essentially because I use image backups quite
a bit when deciding if there's a hardware problem of just an OS
level problem, image the system, do a clean install, see if the
problem goes away, if it doesnt, restore the image and look more
closely at the hardware to work out where the problem is.
I also routinely image a system before upgrading and do occassionally
need to image the new install, restore the original image, to check some
config detail etc that I want to reapply to the new clean install etc.
I test mine, but the majority have "blind faith" untill the time
comes that they NEED to restore. Restoration of the drive
can also take the better part of a day of downtime,
Only if your backup scheme is completely ****ed.
while preventative replacement can
take as little as a couple hours in off-time.
You'd be better or working out why you get such lousy drive reliability.
The Seagate has a 1 year warranty, and was in a computer
that only runs a few hours a week - and lasted less than 3 years.
I used to work for the (then) largest hard drive distributor in Canada.
But didnt manage to work out how the MTBF is determined.
specially those concerning the maximum number of startups/stops
the drive can tolerate before the heads get completely worn.
Wrong again. Its such a round number it cant have been produced
by TESTING, and the number of starts and stops dont produce
any wear of the heads with modern hard drives anyway.
I donīt want to imply that all manufacturers are dishonest per se,
but I can easily see how a given manufacturer can produce different
items, with differents level of quality of design and manufacture.
And these differences *will* impact the useful lifetime of the final product.
Separate matter entirely to the claim that they do reliability
TESTING with domestic appliances.
They dont, and dont with mass market hard drives either to
produce the MTBF or the number of start stop cycles either.
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