12*10.6 Asus rampage extreme III Board advertised as ATX??

Feb 4, 2019
1
0
10
So I recently bought a mid case corsair carbide spec - 05 mid tower compatible with ATX, however as the title explains my board is also advertised as an ATX board but it is one inch wider than a full ATX board 12*9.6, what am I missing here? I checked on part picker and the compatibility was a match. Is there a range for ATX? Any explanations would be appreciated it.

Thank you.
 
The Asus website does list the board as 12x10.6 so they do disclose the true dimension so that you can be sure to accomodate it.

It may not be the answer you want but just because it's a 'standard' doesn't mean a mfr. has to comply when deviations contribute to the product's performance and can be accomodated. Welcome to the world of systems design.