Sata & Hardrive

I'm having some issues with what i think is sata and my hardrives. At one time i had them set up correctly until one of them failed (so i thought). One would stop working and the other would work. It did this back and forth twice. Because of this i have XP installed on both. I would have to go in and selet the correct hard drive to boot from, if i didnt do this it would blue screen. I've tried changing it in the bios but it still does it. I tried swapping the cables around several times with no effect. Any help would be greatly appreciated. Also i get a prompt after the bios loads to hit F4 and change the RAID configuration but when i press it it does nothing.

Thank you