Migrating to RAID1 error

I've been working on this all day to no avail.  It seems like others have found migrating to RAID1 (mirroring) fairly straight forward but this is what I've been trying and getting nowhere with...

 

Purchased a WD 250GB for my Dimension 8400, matched to the WD 250GB factory installed.

Installed the new disk in SATA port 2, (I also tried everything using port 1) booted to Windows, ran Disk Management to partition and format the new drive.  The new drive is recognized by Windows, no problems there.

 

But when I get to the RAID setup I'm getting stuck.  I don't want to or need to reformat or reinstall.

According to the Dell manual and what I've read on forums just go into the BIOS and set the SATA Operation to "RAID On" and then use the Intel utility to set up RAID.  But after I set the SATA Op. to "RAID On" I reboot and the Intel Application Accelerator ROM (v 4.0.0.6211) screen shows up and I get the error:

 

Disk error

Press any key to restart

 

and that is that.  I have to set the BIOS option back to Autodetect to be able to get back into Windows.  Of course then there is no way to set up RAID with the Intel utility unless that BIOS option is set to "RAID On".

 

Thanks in advanced to anyone that can give me any pointers.