Ubuntu 16.04 on a Dell R230

I installed Ubuntu 16.04.1 server onto a fresh Dell PowerEdge R230 with a PERC H710 adapter and two mirrored SAS drives. The install went smoothly but the machine wouldn't boot when it completed. I'd see the error:

Gave up waiting for root device. Common problems:
 - Boot args (cat /proc/cmdline)
   - Check rootdelay= (did the system wait long enough?)
   - Check root= (did the system wait for the right device?)
 - Missing modules (cat /proc/modules; ls /dev)
ALERT! /dev/disk/

by-uuid/d55ef64e-2d0c-4a51-9c6f-20999ee0276e does not exist. Dropping to a shell!

I tried cranking up the rootdelay at the grub edit screen without luck. I finally checked the BIOS settings and noticed that it was set to boot as BIOS compatible. Changing it to UEFI and reinstalling fixed the problem. It now boots like one would expect.