Just a shot in the dark here but which sata connectors do you have your hard drives plugged into. I believe your motherboard has a secondary sata controller for the two extra sata ports which are a different color. I could be mistaken but I believe only the south bridge controlled connectors will work until you install the motherboard drivers. Racking my brain trying to think what it might be and that just occured to me. Also read this
it might help.