Installing motherboard problem

[Ahmadovich]

hey,guys

I need to know which type of screws should be used with those holes on the Mobo to install it to the tray ?
I used #6-32*6 screws which were included with the case
and they are also used to install PSU to the case

but I don't know if this is the right type of screws or not , and I'm worried because I heard that installng wrong type of screws may cause short circuits,

I need also to know... should I use cardboard washers or not ?

Thank you.

 

[JManInPhoenix]

Make sure you do this first - remove all of the standoffs that are screwed into the case for mounting the motheroboard. Place the mother board in position and then use a sharpie to mark through each hole in the motherboard (shows where a standoff will need to be. Remove the motheroboard and place standoffs in all marked holes in the case. Reinsert motherboard to double check that every hole has a standoff under it.

The screws should smoothly hand thread down into the standoffs. Make sure you have enough of the correct threaded screws for each standoff (if the threading doesnt feel right, dont use it!).

After the IO shield is in the case and you mount the motherboard you should be ok as long as the screwhead doesnt extend past the pad on the motherboard.

 

[Deders]

Those are the right kind of screws. You do want to make sure that the stand-off's are in the right place so as not to cause problems from underneath, like J says you should be able to do it by eye.

 

[Ketchup]

You can also do a test-fit of each screw in the standoffs before putting the board in place. It should be pretty easy to tell if the screws have the right "feel" to them when going into the standoffs.

Those screws do look about right though.

 

[silicon]

hey,guys

I need to know which type of screws should be used with those holes on the Mobo to install it to the tray ?
I used #6-32*6 screws which were included with the case
and they are also used to install PSU to the case

but I don't know if this is the right type of screws or not , and I'm worried because I heard that installng wrong type of screws may cause short circuits,

I need also to know... should I use cardboard washers or not ?

Thank you.

when installed the MB on my computer i first made sure the standoffs were in the correct location and the screw i used was slightly different than those you are showing....I did not like the serrated underside of the screw and the largish diameter.

 

[BUnit1701]

when installed the MB on my computer i first made sure the standoffs were in the correct location and the screw i used was slightly different than those you are showing....I did not like the serrated underside of the screw and the largish diameter.

I too try to use screws which are smooth on the underside of the head. Not sure if the serrations would actually damage a motherboard, but judging by the other responses in this thread, apparently not.

 

[BonzaiDuck]

I too try to use screws which are smooth on the underside of the head. Not sure if the serrations would actually damage a motherboard, but judging by the other responses in this thread, apparently not.

That's why there are the little patterns of solder around the holes. The serrations on the underside of the screw-heads are supposed to assure contact with the solder.

Sometimes you'll see a "different kind of hole" among the rest on the motherboard -- usually for the mounting point at bottom-rear of the board or nearest case-rear in conventional ATX mounting schemes. The hole may be designed to fit a plastic or nylon plug that pops into the motherboard and simply provides an unsecured standoff point. In other cases I've seen slotted fittings in the motherboard pan for a slip-in brass standoff with a hole for the mounting screw.

 

[Mantrid-Drone]

I've been interested and involved in this sort of subject for the past few weeks because of a possible problem with the design of the Corsair Carbide 200R case and the Gigabyte MB I've bought.

http://forums.anandtech.com/showthread.php?t=2373523

The issues are covered in that thread so I won't repeat them here now but the question of MB mounting systems and and case screws has always concerned me.

In the Corsair Carbide case the MB is mounted by a mix of fixed and removable standoffs.

The MB mounting screws provided are not like those in the picture ^^^ ie. hexagonal pan head. They have smaller diameter dome heads, wider than the MB mounting holes of course but surely a source of extra stress as a consequence.

As BonzaiDuck touched on I thought the whole purpose of the metal solder 'flower' pattern around each MB mounting point is to ensure good contact with the screw head for grounding. So a smaller head screw is surely not the best choice for this reason either. A flat screw head underside must also be preferable.

I too would like someone to explain the use of the insulating/anti-vibration washers that are provided with some screws stated to be for MB mounting?

Whilst it might make some sense for insulation between the standoff and the bottom of the MB the diameter suggests they're meant to be fitted on top. Surely this interferes or even prevents screw head contact with the grounding 'flower'.

But my main gripe about MB mounting is the stupid lack of consistency in sizing and measurement system being used.

There is bizarre mix of imperial and metric screws used inside cases and actually no standardisation in standoff height, screw lengths, head diameters or design either.

If you're buying replacement standoffs or screws you need to make very sure of their height and screw thread type before purchase.

 

[C1]

Just happened to be reading the book titled "Building a PC" (3rd edition by Stuart Yarnold) and the warning about installing a MB is to make sure that the correct screws are used as if you use screws from some other source and the heads are oversized, you could short-circuit the board.

You should have gotten the standoffs and related screws in a package that comes with the case that was purchased.

If you are not sure about what's going on read your MB manual for installation instructions.

If in doubt, you can purchase a MB mounting stand-off support set/kit in the computer parts section of your local Fry's Electronics store.

Update

Looks like you should be using instead M3 screws (they are a finer thread & not serrated):

http://en.wikipedia.org/wiki/Computer_case_screws
http://www.ebay.com/itm/like/221359773792?lpid=82

 

[Mantrid-Drone]

I prefer M3 screws too, not just because of the finer thread but they seem to be made to a higher standard than some of the 6-32 ones I've had. The ones that were particularly poor in this respect were actually those which came with the Coolermaster case I used for my first build. Two of those provided wouldn't screw into their standoffs because of burrs or bent threads. And yes they were the correct ones for the standoffs.

I was going through my collection of case manufacturer (Coolermaster and Corsair) screws and standoffs along with those I've bought separately and the variety of sizing is, as I said, mind boggling and confusing.

Obviously you should be be able to use those that came with the with case in confidence that they are of the right length for the standoffs also provided. But are they always the best ones to use?

 

[BonzaiDuck]

If it's a matter of "ground," not all the screws will matter.

It had been my observation that most of the brass standoffs (I assume the bundle with cases these days are brass) -- are 6-32 for fitting the threaded motherboard holes. The threads in the standoff for the motherboard screws are often "other than."

Even if you only built one computer and don't service a few more than that, it always pays to collect old computer parts (and screws . . . and standoffs . . ) in your typical vinyl box for that sort of thing. Comes in handy . . .

 

[Mantrid-Drone]

Yes, the standard male standoff case mounting screw does seem to be 6-32.

But for all types the (hexagonal) body height of the standoff varies and can literally be anything dependent on the case. There are some with longer but only part threaded 6-32 mounting screws and smaller bodies. However there seems to be a few standard sizes ie. those most commonly encountered. These are what most of the after-market/high street sell, at least here in the UK.

The two types either have a 6-32 or M3 receiving thread. The 6-32 ones have a shorter body (approx.: 5.5mm) compared to the 6.5mm of the M3. Although either 4mm or 5mm length 6-32 screws (that's how they're sold, in a mix of imperial/metric measurements) can be used, because of the thickness of the MB, a 5mm screw will actually stand proud if you screw it into one of these 6-32 standoffs directly. A 6mm 6-32 screw ie. <1/4" is therefore bordering on being too long for this purpose. Yet 6-32 1/4" screws are being advertised for MB mounting.

M3 receiving standoffs, being longer, can take any screw length in the 4mm - 6mm range.

The important point is these 'standard' M3 and 6-32 receiving standoffs are not the same height and shouldn't be considered interchangeable. We're only talking approx. 1mm difference so it's likely within tolerance or the flexibility of the components and case design to accomdate either. The MB will still line up OK with the main and PCI I/O plates.

But that is not ideal. If the case is provided with 6-32/6-32 m/f standoffs those are what you should use and not 6-32/M3 m/f ones which can easily be bought in error if you haven't realised there is a difference.

The screws used are less important, whether for 6-32 or M3 receiving standoffs, but you should not use ones shorter than those provided and only longer ones if you are certain the standoff can receive them fully.

The screw head design is another matter though and I'm still of the opinion that a head which is, within reason, significantly wider than the MB mounting hole is a better choice than some of the screw head sizes being provided for this job.

I would cite those standard self-tapping case fan screws as a perfect example of screws with a head design barely fit for purpose.