# Motherboard washers



## TBW (Nov 1, 2006)

Quick question- Do those little spacer washers for the motherboard go under the screw on the top side of the motherboard or under the mobo between the mobo and the stand-off's ? 

Been so long since I built a 'puter I can't remember. And what do is their purpose as long as I'm asking ?


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## Nadroj (Jan 23, 2007)

below the mobo and so it does short out on the case


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## Frank4d (Sep 10, 2006)

If we are talking about the little red fiber washers (they look like red cardboard), they are used on top of the MOBO under the screwhead. Their purpose is to provide some cushion so if you overtighten the screws you don't crack the MOBO or scrape off the tin plating (I have never used them though in any of the 30-40 PCs I have built).


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## johnpost (Dec 18, 2005)

it depends on the design of your motherboard and the standoffs.

towards the rear of the motherboard there will be one or more
hole surrounded by metal, those are supposed to have a metal
standoff, a metal screw and no insulating washer because they
ground the motherboard to the case.

in more recent times the other standoffs are frequently
nylon and have plastic clips.

if you have nylon standoffs that take a metal screw on
top then the washer goes under the screw to prevent
shorting traces under the head.

metal standoffs used to be frequent but unless insulating
washers were used top and bottom they shorted your
board. look at your motherboard top and bottom,
if there are linear circuit board traces that would
be touched by a metal standoff or a metal screw
head then you would use them for insulation.
exception is the previously mentioned grounding
point(s) which are usually at the rear and you want both
metal standoff and metal screw to have good contact
with. good modern motherboards may have a metal
donut around other mounting holes, these are 
nongrounding and designed to prevent a metal 
standoff and metal screw from shorting traces,
they are isolated and don't need insulating washers
but it makes no difference on those.

look in your case parts or motherboard parts, if you have 
only one or two metal standoffs they are only for the
rear grounding positions. 

if you are using an old case or parts then getting nylon
standoffs for all but the grounding ones might be better.


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## TBW (Nov 1, 2006)

The cushion sounds reasonable. I thought perhaps it was the "short" thing too, and it seems to me I read something to that effect but it didn't make all that much sense. The stand-off is brass, and your using a metal screw, so how the heck could it prevent a short...

Oh well, question answered. Maybe I'll use them on both sides  

I do remember using them SOMEWHERE when I built my Asus P4P800.

Thanks folks !


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## Frank4d (Sep 10, 2006)

Most important is to make sure there are standoffs only where there are screw holes in the mobo.


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## JohnWill (Oct 19, 2002)

On cheap cases, the dimples that you connect the MB to will sometimes short traces close to the holes. In that case, I put them under the MB. I've never felt the need to put them above the MB, since I've worked on tons of equipment that had PCB's secured with screws, and there was never a need to provide a "cushion" for the PCB. 

Note that more modern MB's now seem to have gotten the right idea and leave a much larger pad for the mounting, so it's unlikely that you'll need these with new builds. It's been a long time since I've done anything but dump them in my washer box.


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## brite750 (Mar 16, 2002)

I dont use them, never have, dont over thighten the mb screws, snug but not too snug, this isnt an engine block


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