Grub Broken with onboard scsi + raid card

[Todd Carter]

Redhat loads fine to a 3ware Raid 5 array and recognizes a scsi drive 
attached to the onboard scsi interface.

After the install and reboot Grub reports a "Hard Drive Error" and quits.

However, if the scsi drive is disconnected from the motherboard then it 
boots fine from the Raid Array.
I would like to be able to use both of these drive interfaces.  Is there 
any way to get them to co-exist?

I have no partitions on the scsi (sda) drive.  I load RedHat and Grub to 
the MBR on sdb (Raid Card) and made sure I changed the drive order in 
the install interface.  The bios hard drive boot order has the 'add-on 
card' then 'scsi drive' in that order.

I've read that Grub can get confused as to what the bios is telling it 
as far as drive information  but am not sure how to proceed
from there. How do I find out what information the bios is giving Grub 
in order to re-map the drive?  If that's what needs to be done then I'm 
unsure about the procedure.

Configuration:
Tyan Thunder k7xPro (s2469) motherboard
onboard Adaptec AIC-7902W SCSI

3ware 8506-4LP pci card configured for Raid 5

Grub device map has:
(fd0) /dev/fd0
(hd0) /dev/sdb

Thanks,
Todd