Asus GD30CI Manuel De L'utilisateur page 20

Connecting microphone and speakers
This desktop PC comes with microphone ports and speaker ports on both the front and rear panels.
The audio I/O ports located on the rear panel allow you to connect 2.1-channel, 4.1-channel,
5.1-channel, and 7.1-channel stereo speakers.
Connecting Headphone and Mic
Connecting 2.1-channel Speakers
20 Chapter 2: Connecting devices to your computer