Asus P1-AH1 - Manual (Page 60)

4-8 Chapter 4: Motherboard info
9. CPU fan connector (3-pin CPU_FAN)
The fan connectors support the proprietary CPU fan. Connect the fan
cable to the connector matching the black wire to the ground pin.
Do not forget to connect the fan cables to the fan connectors. Lack of
sufficient air flow within the system may damage the motherboard
components. These are not jumpers! DO NOT place jumper caps on
the fan connectors!
8. Internal audio connectors (4-pin CD)
These connectors allow you to receive stereo audio input from sound
sources such as a optical drive, TV tuner, or MPEG card.
®
Internal audio connecto
CD
Right Audio Channel
Left Audio Channel
Ground
®
Fan power connector
CPU_FAN
GND
Rotation
+12V