Oxidisation of Seagate & WDC PCBs
in [Storage]
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From: Arno on 13 Apr 2010 17:53 In comp.sys.ibm.pc.hardware.storage Sergey Kubushyn <ksi(a)koi8.net> wrote: > In sci.electronics.repair Arno <me(a)privacy.net> wrote: >> In comp.sys.ibm.pc.hardware.storage Sergey Kubushyn <ksi(a)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. Indeed. >>> 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. Mine is fine on both sides. However there is a quite a bit of contact area that looks and feels silver-plated to me, most notably areound the screws and on the bottom the contacts to the head assembly. Arno -- Arno Wagner, Dr. sc. techn., Dipl. Inform., CISSP -- Email: arno(a)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
From: Sergey Kubushyn on 14 Apr 2010 04:43 In sci.electronics.repair Arno <me(a)privacy.net> wrote: > In comp.sys.ibm.pc.hardware.storage Sergey Kubushyn <ksi(a)koi8.net> wrote: >> In sci.electronics.repair Arno <me(a)privacy.net> wrote: >>> In comp.sys.ibm.pc.hardware.storage Sergey Kubushyn <ksi(a)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. > > Indeed. > >>>> 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. > > Mine is fine on both sides. However there is a quite a bit of contact > area that looks and feels silver-plated to me, most notably areound > the screws and on the bottom the contacts to the head assembly. That makes me wonder why are they silver-plated. It is definitely not the best material longevitywise, especially for such low-level signals. It makes me even more suspicious and adds to the conspiracy theory. --- ****************************************************************** * KSI(a)home KOI8 Net < > The impossible we do immediately. * * Las Vegas NV, USA < > Miracles require 24-hour notice. * ******************************************************************
From: Arno on 14 Apr 2010 11:41 In comp.sys.ibm.pc.hardware.storage Sergey Kubushyn <ksi(a)koi8.net> wrote: > In sci.electronics.repair Arno <me(a)privacy.net> wrote: [...] >>> Those 4 were fine on the top of PCB. Black stuff was underneath, on those >>> pads contacting with springy heads pins. >> >> Mine is fine on both sides. However there is a quite a bit of contact >> area that looks and feels silver-plated to me, most notably areound >> the screws and on the bottom the contacts to the head assembly. > That makes me wonder why are they silver-plated. It is definitely > not the best material longevitywise, especially for such low-level > signals. It makes me even more suspicious and adds to the conspiracy > theory. Well, maybe. However I tend to think that "never attribute to malice what can be adequately explained by stupidity" may apply. These contacts should be gold plated with high quality gold. It is also possible that the HDD vibration (always present with a running HDD) and thermal variation allows the process to creep between the contacts and kill them. Maybe a young, inexperienced engineer was hired to replace an older, experienced (but more expensive one) and that person made a pretty bad judgement call due to inexperience, wanting to save a few cents on the design. I have to say that the last time I saw silver plating as contact protection was in vaccuum tube equipment. Modern electronics typically uses Gold, or Tin for low insertion cycle contacts. I also found a statement on Wikipaedia that silver plated copper, once the copper is exposed in a place, will rapidly corrode all over because of some electro-chemical process. No idea whether this is true or not. Arno -- Arno Wagner, Dr. sc. techn., Dipl. Inform., CISSP -- Email: arno(a)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
From: Rod Speed on 14 Apr 2010 16:13 Sergey Kubushyn wrote: > In sci.electronics.repair Arno <me(a)privacy.net> wrote: >> In comp.sys.ibm.pc.hardware.storage Sergey Kubushyn <ksi(a)koi8.net> >> wrote: >>> In sci.electronics.repair Arno <me(a)privacy.net> wrote: >>>> In comp.sys.ibm.pc.hardware.storage Sergey Kubushyn <ksi(a)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. >> >> Indeed. >> >>>>> 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. >> >> Mine is fine on both sides. However there is a quite a bit of contact >> area that looks and feels silver-plated to me, most notably areound >> the screws and on the bottom the contacts to the head assembly. > That makes me wonder why are they silver-plated. It is definitely not > the best material longevitywise, especially for such low-level signals. Likely just some fool's reaction to the price of gold. > It makes me even more suspicious and adds to the conspiracy theory. Nope.
From: Sjouke Burry on 14 Apr 2010 16:37
Sergey Kubushyn wrote: > In sci.electronics.repair Arno <me(a)privacy.net> wrote: >> In comp.sys.ibm.pc.hardware.storage Sergey Kubushyn <ksi(a)koi8.net> wrote: >>> In sci.electronics.repair Arno <me(a)privacy.net> wrote: >>>> In comp.sys.ibm.pc.hardware.storage Sergey Kubushyn <ksi(a)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. >> Indeed. >> >>>>> 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. >> Mine is fine on both sides. However there is a quite a bit of contact >> area that looks and feels silver-plated to me, most notably areound >> the screws and on the bottom the contacts to the head assembly. > > That makes me wonder why are they silver-plated. It is definitely not the > best material longevitywise, especially for such low-level signals. It makes > me even more suspicious and adds to the conspiracy theory. > > --- > ****************************************************************** > * KSI(a)home KOI8 Net < > The impossible we do immediately. * > * Las Vegas NV, USA < > Miracles require 24-hour notice. * > ****************************************************************** You know of course that the black silver layer is still conductive for low level signals?? |