Motherboard What are the "smaller than mITX" form factors?

[JosephEK]

I've seen terms thrown around like "thin ITX" "Mini STX" "Nano ITX" and "Mini DTX"

I would love to use one of those newer Pentiums with hyper threading for an HTPC and I thought it would be kind of cool to use a really small form factor for it, but I don't know anything about the form factors that are available. Can anybody help enlighten me?

 

[Ceros_X]

Check the sidebar on this Wikipedia article? https://en.wikipedia.org/wiki/Computer_form_factor


Hope it helps!

 

[Arboreal]

A couple of them are more unusual.
Thin ITX is the same footprint (170x170mm) as ITX, but has a height restriction on its components to allow it to go into slim cases - say rack mounted servers.

Mini DTX isn't used at as standard, but ether are some 'funny' mATX boards out there that could be considered as mini DTX.

mATX is 244m x244mm but there are a good number of low end mATX boards that are 'narrow' at 170mm (like ITX) width and only having 2 memory slots.
These come in various lengths from 190 to 220mm depending on how many expansion slots they have.

The shortest ones with 2 slots (170x190mm) could be regarded as mini DTX, which are small enough to go into a mini ITX case that has room for a 2 slot graphics card. Asrock do an H81M-DG4 for example, and there are similar models from Gigabyte and Asus, and also in the newer H110 series.
There has been a long discussion on [H]ardforum about the largest motherboards that can fit an Ncase M1, as it is a '3 slot' case for large graphics cards with deep coolers, and has about 220mm of board space.
Some of the mATX boards are 3 slot, like the Asus H81M-K
They are about 1" / 25mm shorter than a full length card, which also makes them more flexible in other cases.

 

[Jin]

Nexus 5x

 

[jtd871]

Thin mITX was originally designed for use to fit in all-in-one (AIO) PCs where the "case" is integral to the monitor.

 

[Arboreal]

Thin mITX was originally designed for use to fit in all-in-one (AIO) PCs where the "case" is integral to the monitor.

I didn't know that... Makes sense, with limited space to deep the depth at a minimum.