I have a working lenny system to which I would like to add a hot swap sata drive for backup purposes. When I configure the BIOS for AHCI the boot process stops with "bad magic number in super block" on 3 of the partitions. These Partitions are mounted on /home /tmp & /spare. I have searched quite a bit but haven't found much info. When I remove the AHCI from the BIOS it works OK. I feel that I may be getting in over my head.

I really don't want to re-install unless I have to.

System info.
Gigabyte GA-X38-DQ6 m/b - Southbridge ICH9R

Thanks, Bob.

If it was installed while the BIOS was set to ATA, then switching to AHCI will cause problems. This causes a BSOD on Windows. I'm not sure of the exact effect on Linux, but most ppl seem to say it won't boot anymore.
I guess the simplest solution is to reinstall while it's set to AHCI.