OK, I have installed CentOS 6.5 on this beast using parted to make GPT partitions (royal PIA, but done). The machine has three 500G SATA disks with 4K sector sizes.

Partitioned with three partions for each of the main disks:

sda1 => FAT32 => /boot/efi sdb1 => FAT32 => (not presently mounted, but will be a backup copy of /boot/efi).

sda2, sdb2 => /dev/md0 => ext4 => /boot

sda3, sdb3 => /dev/md1 => LVM VG, containing /, /home, swap, soon others

sdc1 => will be an ext4 and will hold backups.

I went into the BIOS and added a UEFI boot option using sda1: "C:\EFI\redhat\grub.efi", but this boots to the grub shell. Doing a

device (hd0) /dev/sd0 root (hd0,1) configfile /grub/grub.conf

boots up the machine, but how do I make it possible to boot the machine automagically?