Lenovo THINKSTATION 4105 - Manual (Page 13)

1 Audio line-in connector Used to receive audio signals from an external audio device,
such as a stereo system. When you attach an external audio
device to your computer, connect the cable to the audio line-out
connector of the device and the audio line-in connector of the
computer.
2 Audio line-out connector (front speaker
connector)
Used to send audio signals from the computer to external audio
devices, such as powered stereo speakers (speakers with built-in
amplifiers), multimedia keyboards, or the audio line-in connector
on a stereo system or other external recording devices.
When used with 5.1 or 7.1 surround speakers, this connector
should be attached to the front left and right speakers.
3 Microphone connector Used to attach a microphone to your computer when you want
to record sound or if you use speech-recognition software.
4 Headphone connector Used to attach headphones to your computer when you want to
listen to music or other sounds without disturbing anyone. This
connector might be located on the front of the computer.
5 Audio line-out connector (subwoofer/center
speaker connector)
When used with 5.1 or 7.1 surround speakers, this connector
should be attached to the center speaker and subwoofer.
6 Audio line-out connector (rear speaker
connector)
When used with 5.1 or 7.1 surround speakers, this connector
should be attached to the rear left and right speakers.
Chapter 3 . Setting up your computer 7