ASRock P55 Extreme4 -- Boot Order Question

[trclac]

I have my Crucial C300 SSD attached to a SATA III Port on the Extreme4 MB, and I have two traditional SATA II HDDs attached to SATA II ports. I have repeatedly set up the BIOS so that the first boot drive is the Crucial SSD and the second boot drive is my SATA II blu-ray ROM. However, for whatever reason, the system continuously tries to boot from one of the SATA II HDDs on start-up. I go back into BIOS and switch the boot selection back to the C300 SSD SATA III, restart, and it boots normally ... until I shut it off and try to boot it again later, when it again tries to boot from one of the SATA II HDDs.

All the hard drives, including the SSD, are set up as AHCI drives.

What am I doing wrong here, or is this a problem with the 1.40 BIOS? What settings should I enable so that the system continuously boots from the SATA III SSD instead of trying to boot from one of the SATA II HDDs?

Thanks.