Asus P5KC - Manual (Page 60)

2-36 Chapter 2: Hardware information
9. CPU, chassis, and power fan connectors
(4-pin CPU_FAN, 3-pin CHA_FAN1, 3-pin CHA_FAN2, 3-pin PWR_FAN)
The fan connectors support cooling fans of 350 mA~2000 mA (24 W max.)
or a total of 1 A~7 A (84 W max.) at +12V. Connect the fan cables to the fan
connectors on the motherboard, making sure 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 CPU-FAN and CHA-FAN 1-2 connectors support the ASUS Q-FAN 2
feature.
10. Serial port connector (10-1 pin COM1)
This connector is for a serial (COM) port. Connect the serial port module
cable to this connector, then install the module to a slot opening at the back
of the system chassis.
The serial port module is purchased separately.
P5KC
®
P5KC Fan connectors
CPU_FAN
CHA_FAN1
GND
Rotation
+12V
CHA_FAN2
PWR_FAN
GND
Rotation
+12V
GND
CPU FAN PWR
CPU FAN IN
CPU FAN PWM
GND
Rotation
+12V
CPU_FAN
PWR_FAN
CHA_FAN1
CHA_FAN2
P5KC
®
P5KC COM port connector
PIN 1
COM1