brassplyer said:
Got a WD Elements 1TB external. This is the first such drive I've seen
that has NO ventilation slots whatsoever. Just a black case. It's my
understanding that cooling is critical for drive longevity. When I run
externals I also have a fan blowing over them - from a distance to
avoid the magnetic field from the fan affecting the drive.
I also have a WD Notebook drive that the interface circuitry died on
so now have it running internally as a SATA drive, so am particularly
leery about this no vent hole construction.
Any thoughts?
The magnetic field from the motor should not affect the platters.
I've done some reading on that, and the situation used to be,
that longitudinal recording is quite resistant to external fields.
This is one of the reasons, that using degaussing coils as a
means to securely erase disks is perilous. The degaussing coil
is likely to damage something mechanically when it is used (so the
drive could be rendered useless from a reuse perspective), but
may not succeed in erasing all the field on the platter. If the
platter is transferred to another housing with working head assembly,
it might be recovered.
Think about those magnets located under the actuator arm (under
the plate in the picture). The field from those can't be entirely
contained by that assembly, so there would be a much stronger stray
field from that. If they were trying to completely contain the field,
they'd have surrounded that thing with annealed mu-metal.
http://www.pcdoctor-guide.com/wordpress/images/6 - open2.jpg
One article I read, mentioned that the new perpendicular recording
used on high density drives (like your 1TB), are more sensitive to
external fields. But the manufacturer has worked on the structures
inside the drive to minimize the effect. In their words, the new
drives are no more sensitive to external fields, than the old ones
were.
They do place brushless DC fans in external hard drive enclosures,
and I haven't read of any rash of erasures. Some enclosures even use
an 80mm mounted underneath the body of the drive, which would surely
have exposed the drive to a small field.
As to what to do with your drive, that depends on how hard it is to
open the enclosure.
The answer to your question is, to not buy products like that in the
first place. I'm a believer in fan cooling, like you are, and to get
the features I want in an external drive, I build up my own with
a raw drive and separate enclosure. That way, I can shop for the
features I want.
(There aren't that many to choose from, and this is a random example.)
http://www.newegg.com/Product/Product.aspx?Item=N82E16817106114
http://images17.newegg.com/is/image/newegg/17-106-114-V01?$S640W$
(This Syba one is a bit more artistic.)
http://images17.newegg.com/is/image/newegg/17-801-047-S05?$S640W$
Retrofitting cooling on your drive, will depend on how difficult it
is to get inside, and whether any warranty is voided by removing a label
stuck over one of the screws. Some of those pre-packaged drive have
hidden screws - if you search the web, occasionally someone will
reveal the secret of how to get them apart without damaging them.
This is the last enclosure I bought - it has a 40mm fan in the
back, and grill in the front. But being IDE, I doubt they're
still shipping these. And this one is actually a 5.25", with
poor provision for s 3.5" drive. But I have placed a hard
drive in it on occasion anyway
Normally, it holds
an IDE DVD burner.
http://www.startech.com/Share/Gallery/Large/IDECASE525U2.Elarge.jpg
Paul
