Maximum PC motherboard height

[SavannahLion]

Tried to find what the maximum specified height requirement for motherboards. Didn't find it or I wasn't looking in the right place. Pulled open one of my PC's and the height seems to be around 4.5" from the top of the card to the motherboard itself (which includes the slot) This is the tallest vertical card mounted on the motherboard. I know there are some monster coolers that probably eek beyond this but I don't have one.


Does anyone know if 4.5" tall is a correct assumption? Can't see this going too far past this size since the board I measured came out of an old (and misplaced) drawer PC case. (Won awards for design and now you don't see drawers on cases, go figure ).

I haven't selected or purchased the motherboard because I'm trying to avoid the dreaded "testing" phase.

[severdhed]

not sure i'm following you here...are you talking about the height of a video card or something?  since video/sound/any random cards are generally generic, they should all be the same height, with the exception of low profile cards of course.

[lilshawn]

internal height is only limited by the internal dimensions of the case. There is no specification for maximum height of any add-in cards but the spacing between is.  though most card manufacturers tend to keep the height low enough to not cause issues.
http://www.formfactors.org/developer/specs/atx2_2.pdf

[SavannahLion]

internal height is only limited by the internal dimensions of the case. There is no specification for maximum height of any add-in cards but the spacing between is.  though most card manufacturers tend to keep the height low enough to not cause issues.
http://www.formfactors.org/developer/specs/atx2_2.pdf

Yeah, I looked over that document. I've been using it to get general measurements without tearing down any of the other PCs. The catch is this specifies only the ATX component height requirements. Not daughter cards. Daughter card specifications (eg PCIe) seem to align with my expectation.

IRT severdhed:

Well.. what I'm talking about is the measurements of your standard ATX board. So a board measures approximately 12" x 9.6". What I don't have a clear picture of is the height off of the board.

I think I'll settle on 4.5" and tack on say... another 1/2" as a margin of safety and go with that.

I don't imagine I'll actually need that much space. But I'm refusing to even select a new motherboard until the cab is two steps from complete.

[severdhed]

well, the height of an expansion card might not be defined as a standard, they metal mounting bracket on the back of it is.  that metal bracket is the same size on all cards, so that they can be mounted in any case.  very rarely is a card any taller than the metal bracket at the back of it (although i have seen a few SATA raid cards with connectors on the top edge, so you would need to take into consideration the space required for the cables)

[SavannahLion]

well, the height of an expansion card might not be defined as a standard, they metal mounting bracket on the back of it is.  that metal bracket is the same size on all cards, so that they can be mounted in any case.

I had not even considered that. Thank you.

[severdhed]

np.  i would leave a little space above the height of the metal bracket, while most cards are not any taller than that, there are quite a few that are slightly taller, perhaps half an inch or so.  i'd probably leave a good inch or so above that height to make sure you have the clearance you need.

you can go to a pc parts site, such as newegg.com and look at video cards for instance. it will show you pictures of all kinds of video cards, all of them seem to be right about the same size as the metal bracket.

 don't forget that the motherboard doesnt typically sit flat on the bottom of whatever it is mounted to, but usually is mounted with some kind of stands.  (i used the bic pen method when mounting a motherboard onto a piece of wood).  also the metal bracket on the expansion cards extends past the motherboard on the bottom, which means you will have to have the motherboard mounted on some kind of stands to raise it high enough for the card to clear, or bend the bracket on the card in order to accommodate it.  i ended up bending the bracket on my video card and drilling a hole through it, and used a screw and part of a bic pen to secure it to the board, since i didn't have anything to attach the top of the card to....this held up very well, even with the motherboard mounted vertically.

[DeLuSioNal29]

Severdhed ... always LOVED that BIC pen mod!  So simple but works great!