Asus V6-P5G31E - Manual (Page 35)

3-7 ASUS V6-P5G31E
4. CPU and chassis fan connectors.
(4-pin CPU_FAN, 3-pin CHA_FAN)
Connect the fan cables to the fan connectors on the motherboard, ensuring
that the black wire of each cable matches the ground pin of the connector.
DO.NOT forget to connect the fan cables to the fan connectors. Insufficient air
flow inside the system may damage the motherboard components. These are
not jumpers! DO.NOT place jumper caps on the fan connectors!
Only the 4-pin CPU fan connector supports the ASUS Q-Fan feature.
5. Optical drive audio connector (4-pin CD)
These connectors allow you to receive stereo audio input from sound sources
such as a CD-ROM, TV tuner, or MPEG card.