Asus M3A boot bios ide/sata question

I just purchased a new asus m3a motherboard, and have tried countless combinations to have my new SATA drive as the bootable drive(just did fresh install of XP pro), and an existing IDE data drive as the backup(it was my old 'D' drive when I had a 2 IDE drive setup on my old mobo). When only the SATA drive(plugged into SATA 1) and IDE CD/R are attached, I can boot no problem. When I attach the IDE HDD(tethered to the CD rom, or by itself) the bios will not allow the SATA to be the bootable drive. The SATA essentially disappears in the boot menu-only the IDE hard drive, and CD/R exist as booting options. When I un-attach the IDE HDD, the SATA appears again in the boot menu. I think I have tried every jumper setting between the CD/R and HDD, but to no avail. I haven't installed any of the mobo CD drivers yet-is this an issue with running XP on such a new mobo? Thanks if anyone can help!
-Rob