Yes that pretty much covers it.
I think I was not clear on the functionality of the EFI modes on this board.
From reading other posts I understood I had to convert the disk to gpt using diskpart.
Looks like I have successfully created the gpt partiton on the RAID card but it wont boot.
Changing it to EFI boot in the BIOS makes no difference it does not see the Sil Raid0 as a bootable partition.
I may have to stick with mbr and create a another partiton in order to get the left over drive space.