Motherboard Standoff Help?

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thepcphysician

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Hi,

I am trying to mount an ASUS M4A78LT-M LE mobo inside an Azza Orion case.

Here's the problem: even though I am using the smallest standoffs I have, the motherboard's ports will not align with the i/o plate. The screw holes on the mobo tray are already "raised" (you can see the pics at the link below), so when I put the standoffs in, the motherboard sits too high in the case.

If I don't put standoffs in, the mobo fits perfectly. However, I have heard that this can lead to a short, although I fail to see why, since the standoffs are also made of metal.

Should I just skip the standoffs? Any help would be greatly appreciated!
 
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I think that means the spacers were built into the case ... so they probably won't cause any trouble.

If you're worried, you could always put a thin nylon washer between the mobo and the case so they won't be physically touching.

thepcphysician

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Oops... forgot the link. ;)

http://www.newegg.com/Product/Image.../black SECC Steel ATX Mid Tower Computer Case
 
I think that means the spacers were built into the case ... so they probably won't cause any trouble.

If you're worried, you could always put a thin nylon washer between the mobo and the case so they won't be physically touching.
 
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thepcphysician

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Success! It POSTed. You were right, the raised holes elevate the solder joints on the back of the mobo so that they don't make contact with the steel case - like having built-in standoffs. Thanks again for your help.
 

ram1009

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I strongly disagree with the suggestion of using nylon washers between the screw impressions and the MB. The circular area around each mounting hole is ground plane and intended to be in contact with the metal of the box. Placing a non-conductor such as nylon between the MB and the metal would limit the amount of ground contact to the threaded portion of each screw where it screws into the bottom plate. That may or may not be enough ground. Poor grounding can cause all sorts of weird anomalies.
 

uh_no

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100% correct. Most people think that they are supposed to prevent contact, but this is in fact incorrect. The motherboards are designed to have metal contacts around the mounting holes which are meant to connect to the metal case, causing the entire case to be pulled to ground. If you electrically isolate the case from the motherboard, there is no guarantee it is grounded, and this can cause all sorts of problems as the person above noted, all sorts of capacitances can actually hurt the performance of the motherboard in certain circumstances, and if at anypoint the motherboard did contact the case, you could short something

case in point: don't insulate the motherboard from the standoffs
 

thepcphysician

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Thanks for your advice, Ram1009 and uh_no. As I started to put in the mobo last night, I had a sort of epiphany; I realized that the whole point of standoffs was to prevent the solder joints on the back of the board from making contact with the backplate *and* to ground the case. So, I actually decided not to put in the washers, and it worked fine. Nice to know you agree with that decision - thanks again everybody. :)
 
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