It always has needed them... Vista picks up some naitivly, but XP always needed it.
I do not belive you will need to install the RAID drivers when you install windows since the boot drive will not be on RAID. The only exception I can see to that is if your BIOS is some-what limited and your only option is to have all or none of the ports RAID enabled. In that case you would still need to Install a RAID driver so Windows can see the drive but the drive itself will not be in a RAID array.
If drivers are needed, XP is very picky and will only take the RAID drivers off of a floppy disk. Vista is much more forgiveable and allows a flash drive, CD, DVD, floppy, or what ever else you might happen to put the driver on.
