HuntKey wide power on the computer version 2.3 Wang

I am a novice knowledge recently asked installed under the wide HuntKey Wang 2.3 version of the computer power supply lines outside the box following are the root of the smaller Round-line with what is the

“outside the box the power cord (?) The following are the root of the smaller Round-line,” I do not understand! May be the front-audio connections, namely:the audio signal to receive pre-audio jack.That power is provided by an add-in, there can be output from the 12-volt DC power supply to some of the liquid crystal display.