Help configuring RAID0 - dmraid with SATA II drives and nvidia nforce 410

[Debbie Deutsch]

Maybe someone can help me figure out how to get RAID 0 up and running under
FC 4.  My system has a pair of SATA II drives and an nforce 410 chipset.  I
have installed the latest nvidia drivers for that chipset (another story -
they are for audio and ethernet).  Currently I have it booting off an
external USB hard drive.  The BIOS is configured to place the two hard
drives in RAID 0 configuration.  It says the RAID array is healthy.  I have
read as many HOWTOs and message threads as I have been able to find on the
subject.  

The hard drives are brand new.  There is no data or partitions from other
operating systems to preserve.  Here is what I have tried.

1. From FC4 (running on the USB drive), try to see the RAID array using
dmraid.  Nada.  (I tried dmraid -s, dmraid -ay, dmraid -b.  That last
command does show the USB drive.)

2. Attempt to install FC4 onto the RAID array.  Disk Druid complains that it
does not see any disks.

I know some people advise to turn off "fake raid" support in the BIOS and
just do software raid.  So, here are my questions:

A) is there any way at all (from inside FC4 when it is running or during
install) to get at the raid array that I have made in the BIOS?

B) if the answer to the above is no, and I need to disable RAID in the BIOS,
do I still use dmraid (because the nv_sata driver is involved) to set up the
array under FC4?  Or can I accomplish everything in Disk Druid during the
install?  Or do I need to set things up in Disk Druid and then activate the
RAID array in dmraid?

C) if the answer to A) is yes, what advantage would there be to disabling
the BIOS RAID anyway?  (I'm just curious.)

When I finally do get this working, perhaps I should write a HOWTO for this
- a real step-by-step cookbook.  OTOH, FC5 is coming soon...

TIA

Debbie