All computers have at least three audio connectors:

• Green: Line out.
• Blue: Line in.
• Pink: Mic in.

On PCs with six-channel audio, two more connectors are required: rear out (black or blue) and center/subwoofer out (orange or yellow). However, not all computers have these outputs!

So the first thing is to look at the back of your PC and see if your computer has these outputs. The PC on Figure 8 has all of them and also digital outputs (as we mentioned, if you want to use digital outputs, read our tutorial on that).

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Figure 8: Audio outputs on a PC.

If your computer doesn’t have these two extra outputs (rear out and center/subwoofer out), you will need to use the line in and mic in plugs. Of course there is a really big disadvantage in using this configuration: you cannot use your microphone or line in inputs and your 5.1 speaker system at the same time. More: if you need to use these inputs – maybe you want to connect a mike to use Skype or MSN Messenger, for example – you will need to unplug your speakers and connect your device, use it, and then plug the speakers back after using your mike or capturing audio. Yes, it is really a hassle. That’s why if you really want to use a 5.1 speaker system you should look for a motherboard that provides separated rear and center/subwoofer outputs, like the one shown on Figure 8.

PCs with eight-channel audio (7.1 format) another plug is required for the middle speakers (this plug is usually grey). On Figure 9 you can see the detail of a motherboard with on-board eight-channel audio.

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Figure 9: Motherboard with 8-channel (7.1) audio.