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Zinc Whiskers Cripple Colorado's Computers

Mr. Christmas Lights writes "While zinc whiskers, small metallic fibers which grow on surfaces that have been electroplated with zinc, aren't a problem for Christmas lights, they can cause serious problems for computers. The Denver Post reports how they caused computer outages for the last three weeks in the Colorado secretary of state's office. This basically halted business and elections document filings. Zinc whiskers are becoming more of a problem as computers electronics get smaller. NASA has a good reference site which includes a interesting PDF summary paper complete with pictures. /.'ers with computer rooms might want to check this out."

8 of 276 comments (clear)

  1. Re:Absolutely no way by McCarrum · · Score: 5, Interesting

    (rolls eyes)

    Where I used to work, we had this issue - in our case they grew from the cheap computer floor panels in the room. The case was so bad, you could see them in direct sunlight, and the flowed in the breeze like grass.

    We had no choice but to go through cleaning, as the underfloor was about to be used for blowing air to new systems, without it, the zinc whiskers would blow free and cause hell on all our systems. As it was, three systems failed in the week after the clean. We don't want to think what would have happened if we didn't clean it.

    It's not bullshit. Get over it. Interestingly, there are very few people who know of this issue, but knowledge is spreading.

  2. we just finished replacing our Data Center's floor by jeremyol · · Score: 5, Interesting

    We are in the final streach for replacing the entire datacenter floor where I work because of zinc Whiskers. We had the underfloor area cleaned for the new A/C that blows from the floor up. We promptly lost 11 power supplies and the total count is up over 20 now. We did verify the presents of zinc whiskers in the dead powersupplies thanks to the onsite electron microscope.
    Thankfully the high temperature never got above 85 degrees so the old A/C was able to keep up.

  3. Maybe not zinc whiskers, but tin whiskers exist by Zarquon · · Score: 4, Interesting

    And are a problem with the new lead free processes.. especially as lead spacing decreases, and the euro lead-free requirement kicks in.

    Agere wrote a good article in Analog Zone, available at http://www.analogzone.com/grnt0216.pdf. It has a good micrograph showing the problem.

    --
    "'Tis great confidence in a friend to tell him your faults, greater to tell him his." --Poor Richard's Almanac
  4. Re:Absolutely no way by Lumpy · · Score: 5, Interesting

    I so agree with you.

    back in college I paid my way as a maintaince guy at a foundry. we had rackmount Pc's that would have almost 1/4 inch of metal/sand dust on the motherboards and the computers were STILL working.

    Cince then I have worked as a freelance consultant and specalist for many different companies that certianly do not have their computers in a "clean room" (machine shops for the best example) and they never EVER have these problems and they are exposed to nasty air + metal. The worst was a water filtration plant I worked at for 7 years where a workstation for monitoring the vats of hydro-flouro-sisicilic acid ( what they put in your water to add flouride) a product that is so corrosive that it eat's through the rubber lined fiberglass tanks within 3 years had, just by the amount released in the air during tank inspections, had eaten almost all the legs off the surface mount chips on the motherboard and it was STILL operating.

    Maybe some really REALLY old mainfraime computers might see the problem in a 20-30 year lifespan that the article suggests, but even the PDP-11 I saw back in college that was retired in the basement but still maintained operating by students did not have any problems like this.

    --
    Do not look at laser with remaining good eye.
  5. Re:You can clean them off... by filledwithloathing · · Score: 4, Interesting

    That is a myth. "Magnetic fields and magnetic storage media do mix, as long as the field isn't really amazingly strong. The field has to be really strong, because it has to exceed the coercivity of the magnetic coating on the storage device. Hard drive platters have a coercivity of a few thousand Oersteds, which means a field of the same number of Gauss is needed to demagnetise them. The ferrite magnet on a computer's PC speaker, assuming it's not shielded, will have a surface field strength of only about a thousand Gauss, so it won't endanger hard drive data even if the drive's right next to it. Even 10,000 Gauss rare earth magnets can't wipe a hard drive if they're not sitting on top of it."

    --
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  6. Re:Absolutely no way by Tony-A · · Score: 4, Interesting

    we had rackmount Pc's that would have almost 1/4 inch of metal/sand dust on the motherboards and the computers were STILL working.

    Contacts that are exposed to a "harsh" environment generally form a very thin non-conductive film due to oxidation and/or corosion. This would also apply to any conductive surfaces. Depending on exactly what gets laid down, what you describe seems completely reasonable. However, something in a "clean" environment can easily be killed by something your self-protected PCs wouldn't even notice.

  7. Re:Absolutely no way by muonzoo · · Score: 4, Interesting

    Well you better start doing your homework.

    I worked for many years on a replacement Air Traffic Control System for Canada and as the project matured, our stage - lab (containing litterally hundreds of machines, a complete lab recreation of the coast-to-coast ATC system) started to experience an MTBF on the power supplies in the equipment that was over an order of magnitude smaller than spec'd by the manufacturer (Hewlett-Packard).

    Since this was a long-term contract that included commitments to deliver over an extended period of time (25 years), the material cost of this problem was VERY significant to the equipment vendor, not the customer. (In other words there was no financial motivation to fail to find fault, quite the opposite; the fault was costing them money.)

    In the spirit of "old HP" they sent us some senior hardware design guys to look at our lab and our environmentals (humidity, temp, pressures, cycles and power suppy spectra) to see what was causing the problem.

    Being about 6 years ago -- I hadn't heard of the Zinc problem yet, and neither had the guys from HP. They took everything back to their labs, including about 6 failed supplies and a couple 'still good ones', some from reserve stock and some from working machines.

    A few weeks later they came back; there was a big meeting -- this was an issue with potentially enormous cost -- including the ultimate customer's representatives.

    I can remember the Project Manager practically spitting his coffee when informed the underlying cause. The 'special ESD safe A/C'd lab' was part of the problem. Thank fully, the final deployed environment had different flooring, so we didn't have to change the sites, just some modifications to the lab.

    This is far from BS -- it's a problem that has cost millions and will likely cost millions more before it's over. But the SEM photos of the failed devices we cool to see.

  8. Re:Absolutely no way by _damnit_ · · Score: 4, Interesting

    I love this kind of stuff. Clueless moderators mod the parent insightful because none of them happen to have any personal experience with the subject. Lack of personal evidence does not constitute a conspiracy. Really, it doesn't.

    I have personally known about whiskers for over five years. It was becoming a potential problem in an old datacenter at work. It is a serious condition that datacenters with critical machines (or contractual obligations) take into account in datacenter design and maintenance. With 5 9's required for a lot of machines (Hitachi, IBM, Unisys, etc) there is little room for allowing electrically conductive dust particles to flow across every board on your machines.

    The other posters have given examples to satisfy the typical /. need for anecdotal evidence, yet you groundlessly claim that the articles anecdote MUST have some other explanation. Why? I am all for being a little skeptical, but there is such little reason for it in this case. Would you begrudge them the opportunity to clean out their under-tile areas? Most of us know how bad those areas can get regardless of the whisker issue.

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    _damnit_

    It's my job to freeze you. -- Logan's Run