First make sure that you have the latest BIOS installed on your motherboard
Try setting a hard drive delay under the SATA configuration and change the boot order and hard drive boot order under the boot tab.
Also on the boot tab disable the boot options that you wont need like boot to network or USB.
Are you using the blue Marvel* ports?
If you do, try disconnecting your optical drive. If it goes thru POST and in to the operating system, disable theboot to optical drives in BIOS.
I have some reports of issues when using the blue ports and an optical unit on the black ports that is being investigated.