[SGVLUG] Calling the brightest of cal tech and other nerds!

[Alex Roston]

I see two issues.

First, you can probably test Tom's supposition as follows:

1.) Remove the power wire that goes from the case to the motherboard. 
This will be a twisted pair that goes from the on/off switch to the 
jumper block on the motherboard where you attach the wire that leads to 
the HD LED, the power LED, etc.,

2.) Shock the case again. I'm guessing the static is arching across the 
contacts of the power switch on the case.

Second, there is another issue. The power switch on the case will only 
turn the power supply off if no operating system is loaded. Once you 
load an operating system, it should take over that circuit such that you 
have to hold the button down for four seconds.

Alex

Tom Emerson wrote:

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>My turn to weigh in on the discussion...
>
>Dustin Laurence wrote:
>  
>
>>On Fri, Dec 22, 2006 at 05:06:39PM -0800, Donald E Gibbs wrote:
>>
>>    
>>
>>>Every time you spark the case you reset.  Okay.  The question was
>>>asked why this happens.  Why doesn't the enclosure protect the
>>>internals.
>>>      
>>>
>>Unless you have an idea of what might be unusual in this situation, I
>>think the discussion is esoteric already.
>>
>>To cut even more to the chase, part of the question is "why is this
>>acting differently than other machines?"  I don't recall ever hearing of
>>other machines rebooting under similar conditions.
>>    
>>
>
>Actually, I believe he said it "shuts down", NOT "reboot", but that's
>only a matter of semantics.
>
>in the lightning-fast pace of computer evolution, you might not have
>noticed that for the last three or four years or so, computers don't
>have "the big red switch" anymore -- (for those to young to know what
>I'm talking about, the original "power" switch on IBM PC's was indeed a
>"big red switch", approximately 1" wide with a throw of 3/4" or more.)
>Instead, the (supposed) "power" switch is a soft-switch that goes to the
>MOTHERBOARD, not the POWER SUPPLY, and essentially generates a signal on
>some trace/line related to the PSU which (as John K. surmised) tells it
>to turn off (or on, as the case may be)
>
>my guess, similar to the magic/more-magic switch(*), is that touching
>the case does indeed cause a "signal" to be induced on the "power
>supply" line to the MB, which in turn instructs the system to shut off.
> I /suspect/ you can mitigate this somewhat by changing the BIOS such
>that the "power switch" needs to be held for 4 seconds before shutting
>off (similar to many laptops)
>
>Tom
>
>(*) I'm impressed, Dustin -- you've related that story a few times at
>the after-after meeting (streetside on Lake...) but never knew it had
>been committed to an actual website...
>
>- --
>Top o' the Blog: latest Suse install in the least likely of places
>http://osnut.homelinux.net/mtblog/ya_index.html
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