While the SATA disk was perfectly visible in fdisk / gdisk it did not show in the Ubuntu installer (14.04).
- Boot from the Ubuntu installer CD and get to the step where it would find the disk. None are listed.
- Click back, then press CTRL + F2 to drop to a shell.
- Type sudo su to become root.
- Type fdisk -l and you should see your drive e.g. /dev/sda.
- Type dmraid -E -r /dev/sda (replace sda if necessary as per the previous step)
- Answer yes, you do wish to remove the dmraid info.
- Press CTRL + F7 to get back to the GUI installer, and continue as normal.