Gateway E-5400 System Manual page 12

Serial port connects to a serial device.
RJ-45 LAN connector lets you connect to a network, and the adjacent
Indicator LEDs show LAN activity (yellow) and 100 Mbit speed (green).
Microphone-in, Audio Line-out, and Audio Line-in jacks connect audio
devices such as speakers, tape players, and microphones.
Secondary video port connects the second monitor interface cable.
Primary video port connects the first (or only) monitor interface cable.
Padlock tab permits the use of a padlock to secure the system. To use the
padlock tab it must be removed from it's shipping position and reinstalled
in the active position, as shown below.
Active position
Shipping position
Thumbscrews must be loosened to remove the cover from the system.
Kennsington lock slot lets you use a cable lock to secure the system.
5
Rear panel