A mainframe which preceded the Unisys Clearpath series of mainframes. These machines were usually powered by Intel processors. The operating system, to me at least, looks like the bastard child of MS-DOS and UNIX. These machines were mostly used in the batch capacity. Green screens and character-based interfaces are standard fare for these machines.
Banks of hard drives are arranged in the system as a disk pack. This allowed for expansion as needed, but if one of the drives in the pack bit the big one, it meant a lot of down time.