mATX or mITX

Solution
I would say both.
Some itx cases seem big enough for mATX but physically wont accept them.
Now, if the case is too small to fit an mATX board you know what it is.
By way of pictures on the internet? Probably impossible unless someone knows what specific case you're looking at.

If you have it physically in front of you? Break out a tape measure and you should be able to figure it out.

If you're just shopping around for cases on the internet? Just look at the specification section on the manufacturer's website.

What's the scenario here?
 

JoeMomma

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Nov 17, 2010
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mITX cases have 2 slots and mATX cases have 4 slots.

If you examine the photo that Gam3r01 posted . . .
mITX motherboards are square and have 4 standoffs in the corners.
mATX motherboards have the same 4, plus 1 in the middle and 2 more standoffs below the slots.