T
Timothy Daniels
CBFalconer said:
Right. Gotta look out for those "paper clips, aluminum foil,
nuts, bolts, etc." And loose piston rings. Those are *such* a
hassle.
*TimDaniels*
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Does it matter whether the HD is installed upside down or not?
Right. Gotta look out for those "paper clips, aluminum foil,
nuts, bolts, etc." And loose piston rings. Those are *such* a
hassle.
*TimDaniels*
K
kony
Right. Gotta look out for those "paper clips, aluminum foil,
nuts, bolts, etc." And loose piston rings. Those are *such* a
hassle.
*TimDaniels*
I can't help but think you're trying to reinvent the wheel here... there
is negligable difference in cooling a drive whether it's facing up or
down, compared to having ample airflow past it. The focus then shifts to
"is there any other benefit to one way over the other". It's not all that
hard to drop a screw or whatever down on a drive, particularly in some
cramped cases, odd situations crawling under a desk instead of unhooking a
gazillion cables to pull the whole machine up where it's more accessible,
etc. The circuit board is simply better protected when it's facing
downwards. Couple that with the face that most cases have the drive holes
positioned so that more drives fit when mounted that way, and what little
difference there is, points towards (circuit board facing downwards) being
the slightly easier, slightly safer alternative.
All that changes with oddly OEM cases, but consider that OEMs aren't
generally concerning themselves with avoiding user damage or the number of
additional drives that can be added, they'd much rather you just left the
case shut.
T
Trent©
Right. Gotta look out for those "paper clips, aluminum foil,
nuts, bolts, etc." And loose piston rings. Those are *such* a
hassle.
*TimDaniels*
You must be single...with no pets! ROTFLMAO !!!
Have a nice week...
Trent
Follow Joan Rivers' example --- get pre-embalmed!
T
Trent©
So dust will hurt the hard drive's "electronics",
but it's OK for dust to settle on the motherboard's
"electronics", on all the add-in cards' "electronics",
on the power supply's "electronics"? Why is the
HD's "electronics" so much more sensitive to dust?
And after you answer that, tell us why HDs aren't
made with an engraving somewhere saying
"This Side Up"?
Because the 'up' side is all relative to the way you position the
CASE.
It doesn't make much sense to mark the 'top' of the drive 'this side
up'...if guys like you are gonna position your tower with the rubber
feet at the top! ROTFLMAO !!!
P.S. Its been fun...but I've had enough. lol
Have a nice week...
Trent
Follow Joan Rivers' example --- get pre-embalmed!
G
Guest
Hokey Pokey said:Well, I figured if I can have it laying down on the
bottom of the case, with the plate side down contacting
the case, then the heat from the HD would be dispersed
through the bottom of the case. Bad idea?
If the plate is what's normally considered the top of the drive, then
it won't help unless the plate almost perfectly flat and made of
aluminum, as it was with older Western Digital Caviars, but even then
you'd need an aluminum case and would probably have to remove any
large labels from the plate and apply thermal grease or silicone
rubber RTV between the plate and case (don't block the vent hole in
the plate -- hard drives are not hermetically sealed). But almost all
drives are now made with stainless steel plates, and stainless not
only conducts heat 90% worse than aluminum does but such plates are
much thinner, plus they're largely thermally isolated from the
aluminum body casting by the sealing gasket. I doubt that conduction
cooling will help except through the sides of the drive, right against
the aluminum casting. But if you try this and see much lower
temperatures, they could be caused not by conduction through the case
but by gravity convection because of the vertical orientation.
T
Timothy Daniels
do_not_spam_me said:(don't block the vent hole in the plate -- hard drives are
not hermetically sealed).
Do you want to review that statement?
http://www.tbwt.com/interaction/pcparts/html/1a.htm
"... If smoke, dust or hair got trapped between the head and the platter, the
hard drive would be ruined. That is why the hard drive is hermetically sealed
against dust, smoke and moisture."
http://www.allaboutcircuits.com/vol_4/chpt_15/6.html
"If the hermetically-sealed environment inside a hard disk drive is contaminated
with outside air, the hard drive will be rendered useless. Dust will lodge
between the heads and the platters, causing damage to the surface of the media."
http://www.atarimagazines.com/startv3n4/stcare.html
"Finally, never, ever open up your hard disk to clean its heads. Hard drives are
hermetically sealed and need no head cleaning"
http://www.wsd1.org/kelvin/Departments/teched/TUTORIAL/harddrv.htm
"The container is open in this illustration; however, it is normally
hermetically sealed to keep out dust."
http://www.microscopy-uk.org.uk/mag...ww.microscopy-uk.org.uk/mag/art98/hdrive.html
"The very close working tolerances is partly why the hard drive has to be
hermetically sealed, as tiny dust particles or any hint of condensation would
interfere with its reliable operation. When I dismantled the drive there was a
small woven pad enclosed, possibly a drying agent, to remove last traces of
moisture."
*TimDaniels*
K
kony
Do you want to review that statement?
http://www.microscopy-uk.org.uk/mag...ww.microscopy-uk.org.uk/mag/art98/hdrive.html
"The very close working tolerances is partly why the hard drive has to be
hermetically sealed, as tiny dust particles or any hint of condensation would
interfere with its reliable operation. When I dismantled the drive there was a
small woven pad enclosed, possibly a drying agent, to remove last traces of
moisture."
In the past (and I don't mean 20 years ago) drives were definitely not
hermetically sealed. The "small woven pad" mentioned in the above article
is quite likely the filter used to keep the dust out while allowing air
I/O to equalize pressure, which kept the head at closer to constant
distance from platter. I can see from the HDD manufacturer links that
some (if not all) are now sealed, but I remember plenty of people were
claiming ALL drives were hermetically sealed back when all drives clearly
weren't.
If I were guessing, at some point the drive casing was reengineered to
expand in such a manner to increase internal volume, keep the interior
pressue within tolerance. That guess may be wrong but "something" has
changed, as far more (if not all) do now appear to lack not only the vent
hole, but also the required filter inside.
Does this mean that ALL drives are now hermetically sealed? Maybe, I
don't recall seeing any drives in the past 2 or more years with the vent
holes, but I don't recall "looking" for vent holes either.
T
Timothy Daniels
kony said:Does this mean that ALL drives are now hermetically sealed?
Maybe, I don't recall seeing any drives in the past 2 or more
years with the vent holes, but I don't recall "looking" for vent
holes either.
I'd bet that they're all hermetically sealed now, considering
just the range of temperatures and other ambient conditions a
PC must endure - no antiseptic air conditioned rooms for the
hard drives anymore. Think of the humidity that a HD could
inhale as it cooled off after shutdown in rainy weather or in a
bathroom, and then think of the effects of the subsequent
condensation inside the casing. In the hard drive described
in one of the articles, I suspect that the "pad" contained a
dessicant - very much like the small pad of dessicant that is
packed with camera equipment - to absorb any humdity that
may have been ambient during manufacture.
*TimDaniels*
N
Noozer
Timothy Daniels said:Do you want to review that statement?
No reason to... Not all drives are sealed.
G
Guest
Timothy Daniels said:Do you want to review that statement?
www.tbwt.com/interaction/pcparts/html/1a.htm
"... If smoke, dust or hair got trapped between the head
and the platter, the hard drive would be ruined. That is
why the hard drive is hermetically sealed against dust,
smoke and moisture."
www.allaboutcircuits.com/vol_4/chpt_15/6.html
"If the hermetically-sealed environment inside a hard
disk drive is contaminated with outside air, the hard
drive will be rendered useless...
www.atarimagazines.com/startv3n4/stcare.html
"Finally, never, ever open up your hard disk to clean its
heads. Hard drives are hermetically sealed..."
www.wsd1.org/kelvin/Departments/teched/TUTORIAL/harddrv.htm
"The container is open in this illustration; however, it is
normally hermetically sealed to keep out dust."
www.microscopy-uk.org.uk/mag/indexmag.html?
www.microscopy-uk.org.uk/mag/art98/hdrive.html
"The very close working tolerances is partly why the hard
drive has to be hermetically sealed,...
You've cited many sources -- none of them authorative, such as from a
hard drive manufacturer. Here is what the Western Digial "Caviar
WDAC2200 Technical Reference Manual" says, p. 22:
"3.2.6 Air Filtration System
It is absolutely essential that air circulating within
the drive be free of particles. The HDA is assembled in
a Class 100 purified air environment, then sealed with
tape. To retain this clean environment, the Caviar is
equipped with two filters. One traps any particles which
may be generated during head landings or take-offs.
Mounting the recirculating filter next to the disk places
the filter in the direction of the air flow. This
strategic placement of the filter allows the rotating
disks to act as an air pump forcing air through the
recirculating filter. A second filter, the breather
filter, cleans any external air entering the HDA. The
breather filter also equalizes the internal and external
air pressure. The breather filter is located on the
bottom of the HDA."
On p. 19 of this manual is an exploded drawing of a hard drive
assembly, and it shows a "BREATHER (MEMBRANE) FILTER" that goes on the
bottom of the casting, next to the "SERVOWRITER SEAL".
This WD manual is very old, copyright 1992, and you could argue that
drives have changed considerably since then (for one, WD no longer
seals drives with tape around the perimeter, except for the servo
writer hole), but if you look at something like their WD800JB-00FMA0,
manufactured in Jan. 2004, you'll find a breather hole on the left,
just next to the jumper setting diagram, and newer Maxtors have the
hole on bottom, near the rear. And while it's not an authoritative
source,
http://computer.howstuffworks.com/hard-disk2.htm shows some pictures
of a WD drive, including the breather filter on bottom:
http://static.howstuffworks.com/gif/hard-disk5.jpg
I don't know if the breather filter blocks moisture or not, but I
can't imagine the internal bag of dissicant being useful for long if
moisture could pass easily into the drive because those bags can't
absorb much -- the far larger ones found in car air conditioners have
a capacity of just 200 drops, and old Maxtors (maybe Miniscribes,
which Maxtor later bought) had the final assembly done with dry
nitrogen (I don't know whether the atmosphere was 100% nitrogen or if
nitrogen was pumped into the drive). Does anyone know if the heat
from the operation of the hard drive dries out the dissicant?
So? That hole may not go through to the platter chamber
but merely ventilate the back of the circuit board.
I can't think of a single reason to use a hole for that purpose since
circuit boards are mounted with some space between them and the their
drive's body, with only some foam acoustical between them, and the
foam isn't leakproof.
T
Timothy Daniels
do_not_spam_me said:You've cited many sources -- none of them authorative,
such as from a hard drive manufacturer.
See my posting earlier today in which I report my
conversation with Maxtor's senior tech rep("Brian").
He claims that all current Maxtor drives are hermetic-
ally sealed. When I asked if that meant for gaseous
intrusion (air and moisture) - since being explicit
never hurts - he said yes. He also said that he
remembers one drive "a while ago" which had a vent
that just allowed air to circulate behind the circuit
board but not into the platter chamber.
Here is what the Western Digial "Caviar
WDAC2200 Technical Reference Manual" says, p. 22:
"3.2.6 Air Filtration System
It is absolutely essential that air circulating within
the drive be free of particles. The HDA is assembled in
a Class 100 purified air environment, then sealed with
tape. To retain this clean environment, the Caviar is
equipped with two filters. One traps any particles which
may be generated during head landings or take-offs.
Mounting the recirculating filter next to the disk places
the filter in the direction of the air flow. This
strategic placement of the filter allows the rotating
disks to act as an air pump forcing air through the
recirculating filter. A second filter, the breather
filter, cleans any external air entering the HDA. The
breather filter also equalizes the internal and external
air pressure. The breather filter is located on the
bottom of the HDA."
On p. 19 of this manual is an exploded drawing of a
hard drive assembly, and it shows a "BREATHER
(MEMBRANE) FILTER" that goes on the bottom
of the casting, next to the "SERVOWRITER SEAL".
This WD manual is very old, copyright 1992, and you
could argue that drives have changed considerably since
then (for one, WD no longer seals drives with tape
around the perimeter, except for the servo writer hole),
but if you look at something like their WD800JB-00FMA0,
manufactured in Jan. 2004, you'll find a breather hole on
the left, just next to the jumper setting diagram, and newer
Maxtors have the hole on bottom, near the rear.
Why didn't you just call Western Digital? They have an
800 number. Concerning Maxtor HDs: I have several
DiamonMax Plus 9s and a 17GB Maxtor made at the end
of 1998, and I can't find a vent hole anywhere on them.
If there is a vent hole, it must be hidden under the circuit
board, but that would be contrary to what Maxtor's reps
told me.
And while it's not an authoritative source,
http://computer.howstuffworks.com/hard-disk2.htm shows
some pictures of a WD drive, including the breather filter
on bottom:
http://static.howstuffworks.com/gif/hard-disk5.jpg
I don't know if the breather filter blocks moisture or not,
but I can't imagine the internal bag of dissicant being
useful for long if moisture could pass easily into the drive
because those bags can't absorb much -- the far larger
ones found in car air conditioners have a capacity of just
200 drops, and old Maxtors (maybe Miniscribes, which
Maxtor later bought) had the final assembly done with dry
nitrogen (I don't know whether the atmosphere was 100%
nitrogen or if nitrogen was pumped into the drive). Does
anyone know if the heat from the operation of the hard
drive dries out the dissicant?
I can't think of a single reason to use a hole for that purpose since
circuit boards are mounted with some space between them and the their
drive's body, with only some foam acoustical between them, and the
foam isn't leakproof.
Well, that means that you can't think of a single reason to use a
hole for that purpose. But is that an argument for there being no
hermetic seal on the platter/arm chamber?
*TimDaniels*
D
D. Rogers
I have an easy solution for you, why don't you just turn your case upside
down?
down?
P
Paul L
Ive got an old caviar sep97 that has 4 vent holes in an x shape about .25"x
..25" on a raised area of the top with what looks like a filter beneath them
..25" on a raised area of the top with what looks like a filter beneath them