When our new storage server arrived last week, I wanted to skip use EFI t0 boot this system. It requires en EFI capable system, which this Intel server mobo is capable off.
The CentOS installer doesn't grasp an GPT partition table (needed to enable > 2TB partition tables), so I installed manually. Well.. That didn't go to smooth. Manually installing CentOS, and the GPT partition table was, looking at it afterwards, the least of my problems.
Booting the system was. The system was throwing me into an EFI shell, instead of booting the system. After doing some RTFM on EFI the issue became clear : The EFI BIOS wasn't seeing the controller, because the BIOS on the Areca RAID card isn't EFI capable, but only supports plain old BIOS.
End of story. Areca isn't going to provide an EFI BIOS, because no OS supports it. No OS supports it because no EFI BIOS is avaiable. You get the point… So, back to a plain old MS-DOS partition table.