A portable computer case whether in a closed state or open state permits a user to exercise control and monitor certain operating features. The user may toggle a control switch to place the computer system in a secondary operational mode, determine when a computer system is in a secondary operational mode, and adjust a digital master volume control during the secondary operational mode. The portable computer system includes a status indicator for indicating when a computer is in a secondary operational mode, digital master volume control buttons operable in a secondary operational mode, and a control switch for placing the computer system in a secondary operational mode. The status indicator, volume control buttons, and control switch are preferably provided on a top surface of the bottom shell of the portable computer for convenient access by a user. As such, a user is capable of placing the computer system in a secondary operational mode and determining when the computer system is in a secondary operational mode without opening the portable computer case. A user is also capable of adjusting volume control during a secondary operation mode without the need to access a plurality of volume controls, sort through software to adjust the volumes of the audio sources, or open the portable computer case to visualize volume controls for the audio sources on the main display screen.