DISKS NOT AVAILABLE FOR PARTITIONING

WE HAVE INSTALLED SCO UNIX VER. 5.0.4 ON A COMPAQ PROLIANT 1600. THE TOTAL DISK SPACE IS SUPPOSED TO BE 27GB OF 9GB. WE ARE ONLY ABLE TO SEE 9GB. WE ARE THEREFORE UNABLE TO PARTITION. WHAT ARE WE NOT DOING CORRECTLY?