Phillip Corcoran :
Maybe you first have to highlight the field you want to change?
Yes. You use the up/down keys to highlight the drive. When you are highlighting the drive you want to change, you're supposed to push + or - to move it up or down in priority. But neither of these keys does anything.
My only speculation is that there is a built-in feature that prevents you from moving a non-raid array ahead of a raid array before changing the bios settings from raid to ahci? Because all I did was clone the raid1 to an ssd with Acronis, then reboot. I didn't change any bios settings.