mobo does not autodetect sata drive

[mojo_builder]

I have a Gigabyte GA-K8N-SLI. One of my two WD SATA (RAID 0) drives failed. Click Click Whirr. So i bought two new Samsung 250GB SATA drives. When i bring up CMOS, it does not autodetect my drives. I have the SATA and SATA RAID setting enabled on my mobo, but i get "PXE-61" error when i enter the RAID utility (f10). As troubleshooting, i tried just to detect my old WD (the one that did not fail), and the mobo did not detect that one either.

Do i need load a driver somehow? my BIOS is the most current for this board. I have a hunch i am just missing a step here, but as i am a noob at this, i am lost...

please help.

 

[mojo_builder]

in case anybody cares, it was not detected until i reset my BIOS to defaults, then drives were detected as SATA drives.

hope that helps someone else.