How do I mount my asus z87-a?

Solution

That looks like a typo; the manual says "Place eight screws into the holes indicated by circles to secure the motherboard to the chassis", but the picture directly below that, on the same page, only shows 6 highlighted holes. Just screw it down using those 6 and you'll be fine.

That looks like a typo; the manual says "Place eight screws into the holes indicated by circles to secure the motherboard to the chassis", but the picture directly below that, on the same page, only shows 6 highlighted holes. Just screw it down using those 6 and you'll be fine.
 
Solution