Dell Latitude D630C (Late 2008) - Manual (Page 30)

30 About Your Computer
MODEM CONNECTOR (RJ-11)
USB CONNECTORS
SERIAL CONNECTOR
VIDEO CONNECTOR
AC ADAPTER CONNECTOR
Connect the telephone line to the modem connector.
For information on using the modem, see the online modem
documentation supplied with your computer (see "Finding
Information" on page 13).
Connects USB devices, such as a mouse, keyboard, or
printer.
Connects serial devices, such as a mouse or handheld device.
Connects video devices, such as a monitor.
Connects an AC adapter to the computer.