Greetings,
I haven't looked at your boards documentation specifically, but...
-Enabling RAID in BIOS doesn't mean you will see a "press "ctrl+I to load the RAID Config Utility during POST
-May not prompt, load or display (even if you press the correct key combination) if you don't have at least two disks connected to the ports the RAID controller supports
-Timing is everything and sometimes missing the window will keep the RAID Config Utility from loading if you don't press the keys at the right time
So, do you have at least 2 drives connected to the interface supported by the controller? You haven't stated this, so we don't know for sure.
Thanks