never never install your OS on raid anything. asking for trouble.
DO use raid 0 for your work drives and render to drives. this is a must for serious work.
if working in HD (real HD not HDV) you will need raid 0 anyway to even ingest, much less work with it.
so a proper set up would look like this
C: OS and software single drive
E: single drive for capture/scratch/work (or raid 0 2-4 drives)
F: single drive for final render output (never read and write to the same drive) or again Raid 0 2-4 drives.
lastly rather than onboard raid get a quality raid controller like Areca or Intel.