Dell OptiPlex 330 User Manual page 38

8 VGA video
connector
9 serial connector
38
Desktop Computer Views
Connect the monitor's VGA cable to the VGA connector on
the computer.
On computers with a video card, use the connector on the
card.
Connect a serial device, such as a handheld device, to the
serial port. The default designation is COM1 for serial
connector 1.
For more information, see "System Setup Options" on
page 80.