Installing one or more Hard Discs on a Asus M4At85M motherboard

Attach the Hard drive you'll use for the O/S 1st, usually on Sata port 0, then check to be sure it is registering in the bios then install the O/S, then install the motherboard drivers, then do O/S updates. Then when that is all done set restore point and shut off system and install other hard drive. Be sure it registers in Bios then format it if needed, and you're done.