Medley Raid Card Sil-680 in Compaq EVO510 XP, Help please.

The Silicon Graphics Medley ATA133 Raid card is set up to Mode 1 and I have Mirrored an identical compaq 40Gb HDD.
So the card works and so does another!
When either of the HDDs is connected to the motherboard it boots up and there is a C and F drive if the 2nd HDD is conected to the raid card, D & E being CR/DVD & ZIP.
When both HDDs are connected to the raid card it reports a disk error and requests a 3 finger salutation (<CTRL><ALT><DEL>).

I have looked at the BIOS, in this configuration there is no C drive Listed in the BIOS setup, but the SIL-680 is seen as an option in the BIOS Controller Order as is the Integrated IDE

INCOMPLETE RAID SET message and request for F5
Can I change the BIOS to BOOT from this card as this is what I think the problem is!

COMPAQ give me unbranded if this is typical!
Alan