RAID-1 Question

["Ashley M. Kirchner" <ashley@xxxxxxxxxx>]

   I have a server that has build-in (in BIOS) the option to use either 
Adaptec or Intel based RAID.  We're going to use it as a RAID-1 (and 
I've opted to use the Adaptec setup.)  However, I'm wondering two things:

   1. Should I use the BIOS to create/manage my RAIDs or should I let 
linux do that for me?

   2. Can I add drives to the RAID in the future and simply GROW it, 
without losing information?  Or am I going to be adding more RAID 
volumes as I add pairs of drives?

   The board is a SuperMicro SuperServer 7045B-8R+ with the matching 
7045B-TR+ chassis.

   -- A