Raid 1 trouble on sil 3114 (A8N SLI-Deluxe)

On one of my friend's computers, I built a Raid 1 array using two SATA drives plugged into the onboard silicon image 3114 controller. We installed WinXP X64 and all was fine.

now because certain games wont run in 64 bit mode (driver issues and troubles) we've decided to dual boot with WinXP 32 on a PATA drive.

here's the problem:

Suddenly, the sil3114 RAID controller no longer recognizes the RAID Array, and says 'Invalid Raid Drive'. It DOES recognize each drive individually, yet it does not allow for a rebuild of the array....however i CAN delete the RAID set.

must I delete the Set first, in order to rebuild the array?

(on a side note, if i plug them into the standard SATA ports and use NVRAID, I can build the raid set-- and will do so if i cant figure out what went wrong with the sil3114 controller.)