ATX (12"x9.6", 305mm x 244mm). ASUS features. Slot position 4 : PCI-E x16 (Gen3 x16 Link), automatically switch to x3 if slot 8 is occupied link slot position 5 : PCI-E x8 (Gen3 x8 Link). slot position 8 if slot 7 is occupied: MIO sound card slot.
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