Most enthusiast look at the standard ATX motherboard because it usually includes more features than their little brothers mATX or mITX. Over the past several generations of motherboards, that has been changing to where a new mATX motherboard can include nearly every feature that a standard ATX motherboard can. However, due to the size difference there are a few things that are cut out, mainly extra SATA/SATA-Express ports and support for Three-way SLI or CrossFire. Out of ASUS’ nine different Intel Z270 motherboards, there is only one that is a mATX board, the ASUS ROG STRIX Z270G Gaming.
Any major computer upgrade generally requires a full software reinstall too. No so if you heed the advice in the guide to Upgrading a Motherboard without Reinstalling. PCSTATS Tips