Converting XPS400 Intel 82801 AHCPI SATA to SATA RAID?

Several of Dell's machines, including XPS400, use the Intel 82801 disk
technology, which can be configured for non RAID AHCPI as well as RAID. If
you have built partitions using AHCPI, is there a straightforward way to
convert those over later to RAID, or do you have to start from scratch and
build a new volume?

Is the Dell RAID technology journaling at the block level? In other words,
if I lose power and the disks are left in inconsistent state, will Dell try
to rebuild the entire disk, or just the specific blocks that have changed
since the last synchronization point?

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Will