[SGVLUG] If not static - then possible grounding or miswired power button

[Robert Leyva]

Another thought:

Many motherboards understand the power off as a +5v on the power input
pin, which is a button or switch on the front of the system.

You may have to switch the  connection on the motherboard so the polarity
is changed. Another idea would be to use two screws and a piece of wire to
ground the "main" case to the "front" case, and see if that helps, as you
would then be effectively grounding both parts together.


> On 12/22/06, John E. Kreznar <jek at ininx.com> wrote:
>>
>> > ... static electricity keeps shutting down a computer we recently
>> > built ...
>>
>> What do you mean "shutting down"?  Does it simply freeze as though
>> something is going into a tight loop, or does power get shut off?
>
>
> It just shuts off. I rub socks on carpet, touch front of case, system
> completely shuts off. Doesn't freeze. Last motherboard I tried would
> restart.
>
> Have you probed anything with a 'scope?  If the power supply is
>> turning off, it must be being commanded to do so, and it would be
>> interesting to investigate the source of the command.
>
>
> Probed with a scope? Hm, don't think so.
>
> I once added memory (256 KB to a Microdata 3200 -- big stuff in the
>> '70s) which turned the computer into a veritable noise detector --
>> extremely sensitive to static discharge.  Turned out to be a design
>> flaw in the CDC memory.  I fixed it by rebuilding the refresh circuit.
>
>
> I tried with a different motherboard + different RAM ... still did it.
>
>
>
> --
> Matthew Gallizzi
>


-- 
"Knowledge is Power" -- Francis Bacon

Robert Leyva
mrflash818 at geophile.net