Oxidisation of Seagate & WDC PCBs

[Arno]

In comp.sys.ibm.pc.hardware.storage Sergey Kubushyn <ksi@koi8.net> wrote:

In sci.electronics.repair Sergey Kubushyn <ksi@koi8.net> wrote:

Just took a brand spanking new WD5000AAKS drive out of sealed bag with
silica gel and all that stuff. The PCB is all _SILVER_ plated, no gold. And
that silver is almost totally black right out of the bag.

Not good. Silver really is unsuitable for modern, low voltage,
electronics. The last WD disk I bought (a WD5000AADS, 500GB
Caviar Green) had mixed gold and silver plating and the
silver plating was completely fine, on both sides of the
PCB.

Something is fishy here.

Arno

In sci.electronics.repair Arno <me@privacy.net> wrote:
In comp.sys.ibm.pc.hardware.storage Sergey Kubushyn <ksi@koi8.net> wrote:
[...]
That suicide also can happen when some old file that was not accessed for
ages is read. That attempt triggers the suicide chain.

Yes, that makes sense. However you should do surface scans on
RAIDed disks regularly, e.g. by long SMART selftests. This will
catch weak sectors early and other degradation as well.

I know but I simply didn't think all 3 drives can fail... I thought I have
enough redundancy because I put not 2 but 3 drives in that RAID1... And I
did have something like a test with regular weekly full backup that reads
all the files (not the entire disk media but at least all the files on it)
and that was that backup that triggered disk suicide.

Anyway lesson learned and I'm taking additional measures now. It was not a
very good experience loosing some of my work...

Yes, I can imagine. I have my critical stuff also on a 3 way RAID1,
but with long SMART selftests every 2 weeks and 3 different drives,
two from WD and one from Samsung. One additional advantage of the
long SMART selftest is that with smartd you will get a warning
email on every failing test, i.e. one every two weeks. For additional
warning you can also run a daily short test, e.g..

No matter what you do you can not prevent an occasional disaster One
MUST remember that "backup" in not a noun but a verb in imperative.

BTW, I took a look at brand new WDC WD5000YS-01MPB1 drives, right out of the
sealed bags with silica gel and all 4 of those had their contacts already
oxidized with a lot of black stuff. That makes me very suspicious that
conspiracy theory might be not all that crazy--that oxidation seems to be
pre-applied by the manufacturer.

Urgh. These bags are airtight. No way the problem happened on your
side then. My two weeks old WD5000AADS-00S9B0 looks fine on the top
of the PCB. I think I will have a look underneath later.

Those 4 were fine on the top of PCB. Black stuff was underneath, on those
pads contacting with springy heads pins.

---
******************************************************************
* KSI@home KOI8 Net < > The impossible we do immediately. *
* Las Vegas NV, USA < > Miracles require 24-hour notice. *
******************************************************************

--
Arno Wagner, Dr. sc. techn., Dipl. Inform., CISSP -- Email: arno@wagner.name
GnuPG: ID: 1E25338F FP: 0C30 5782 9D93 F785 E79C 0296 797F 6B50 1E25 338F
----
Cuddly UI's are the manifestation of wishful thinking. -- Dylan Evans

 

[Jeff Liebermann]

On 30 Apr 2010 23:57:32 GMT, Arno <me@privacy.net> wrote:

In comp.sys.ibm.pc.hardware.storage Sergey Kubushyn <ksi@koi8.net> wrote:
In sci.electronics.repair Sergey Kubushyn <ksi@koi8.net> wrote:

Just took a brand spanking new WD5000AAKS drive out of sealed bag with
silica gel and all that stuff. The PCB is all _SILVER_ plated, no gold. And
that silver is almost totally black right out of the bag.

Not good. Silver really is unsuitable for modern, low voltage,
electronics. The last WD disk I bought (a WD5000AADS, 500GB
Caviar Green) had mixed gold and silver plating and the
silver plating was completely fine, on both sides of the
PCB.

I just removed the PCB from a WD200EB-75CSF0 20GB drive. Tin plating
on both the PCB contacts and the mating pin array going into the HDA
assembly. No gold or silver.

However, there's one extra item that hasn't entered the discussion.
There was a sheet of foam something between the PCB and the HDA. In
this case, it was quite clean and dry, but it wouldn't take much for
most any liquid to get absorbed by the foam and rot out the board.
There was a cut-out hole around the connector area, so there was no
common points of contact, but it was close enough that any volatiles
would certainly enter the connector area.

--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com jeffl@cruzio.com
# http://www.LearnByDestroying.com AE6KS

 

[Sergey Kubushyn]

In sci.electronics.repair Jeff Liebermann <jeffl@cruzio.com> wrote:

On 30 Apr 2010 23:57:32 GMT, Arno <me@privacy.net> wrote:

In comp.sys.ibm.pc.hardware.storage Sergey Kubushyn <ksi@koi8.net> wrote:
In sci.electronics.repair Sergey Kubushyn <ksi@koi8.net> wrote:

Just took a brand spanking new WD5000AAKS drive out of sealed bag with
silica gel and all that stuff. The PCB is all _SILVER_ plated, no gold. And
that silver is almost totally black right out of the bag.

Not good. Silver really is unsuitable for modern, low voltage,
electronics. The last WD disk I bought (a WD5000AADS, 500GB
Caviar Green) had mixed gold and silver plating and the
silver plating was completely fine, on both sides of the
PCB.

I just removed the PCB from a WD200EB-75CSF0 20GB drive. Tin plating
on both the PCB contacts and the mating pin array going into the HDA
assembly. No gold or silver.

However, there's one extra item that hasn't entered the discussion.
There was a sheet of foam something between the PCB and the HDA. In
this case, it was quite clean and dry, but it wouldn't take much for
most any liquid to get absorbed by the foam and rot out the board.
There was a cut-out hole around the connector area, so there was no
common points of contact, but it was close enough that any volatiles
would certainly enter the connector area.

20Gb sounds like an old drive. Those were made before this "invention."

My brand spanking new drive was purchased from Amazon 4 days ago and the
manufacturing date is something like a month back. I bought it for a router
I'm building for my recently acquired /28 CIDR IP block on Intel D510MO
Athom board and Intel dual gigabit ethernet adapter (BTW, I highly recommend
that motherboard--it is a small miracle in a huge heap of manure selling
these days.) That means it is _ABSOLUTELY_ the "latest and greatest," not
something dug out of old junk heap. And it is retail.

That means it definitely comes like this right from the manufacturer. I have
serious doubts that it got that tarnished by a mere negligence. They
supposed to have clean rooms there and those drives are packed in airtight
bags. I have a lot of silver plated parts at home in usual zip lock bags and
even without any bags and they don't get this black in years less for a mere
month...

---
******************************************************************
* KSI@home KOI8 Net < > The impossible we do immediately. *
* Las Vegas NV, USA < > Miracles require 24-hour notice. *
******************************************************************