At 07:30 AM 2/21/99 -0600, you wrote:
>I am installing a motherboard (Soyo SY5EMA)for the first time and cannot
>figure out how the grounding works.  Do one or more of the screws that
>attach the board to the case make contact and ground the board to the case
>or are all the screws carefully insolated by using plastic stand-offs or
>plastic washers?  Do the power connectors play a role in grounding the
>board?

Oh, your question may open a big can of worms, but I'll give you my $.02.
Only one screw is needed to ground the MB.  There may be a few holes to
choose from for this.  Use one that has a silver ring or star pattern
around it.  My opinion will differ from others who will say "if they put a
ground contact on any hole, it should be grounded".  So read them all, and
make your own decision, but one ground point MUST be used.  Also, every
mounting hole that aligns with any chasis mount should be used.  Plastic
stand-offs must be used so as to isolate the hundreds of other connections
on the MB.

The power connectors do play a role in grounding, but not really for noise
(electrical noise) immunity.  You need one "ground" for electrical
interference (noise) to go to, and one "ground" for signals to return
(sometimes called "return", or "common"), this one is in the power connector.

HTH


J. Paul Jones
[log in to unmask]
http://www.mindspring.com/~jpjcet/

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