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Chapter 4: Motherboard Connections
4.3 Headers and Connectors
Fan Headers
There are seven 4-pin fan headers (FAN1 - FAN7) on the motherboard.
All these 4-pin fan
headers are backwards compatible with the traditional 3-pin fans. However, fan speed control
is available for 4-pin fans only by Thermal Management via the BMC interface. Refer to the
table below for pin definitions.
Fan Header
Pin Definitions
Pin#
Definition
1
Ground
2
2.5A/+12V
3
Tachometer
4
PWM_Control
Speaker Header
Pin Definitions
Pin#
Definition
1
5V
2
No Connection
3
No Connection
4
Speaker
Speaker Header
A speaker header, located at JD1, can be used in conjunction with an external speaker
(optional). Use an appropriate cable to connect this header to an external speaker or buzzer
for support of BIOS beep codes and system alarms. Refer to the table below for pin definitions.
S-SGPIO Header
The S-SGPIO (Serial General Purpose Input/Output) header (S-SGPIO1) is used to
communicate with the enclosure management chip on the backplane. Refer to the table
below for pin definitions.
S-SGPIO Header
Pin Definitions
Pin#
Definition
Pin#
Definition
1
No Connection
2
No Connection
3
Ground
4
Data
5
Load
6
Ground
7
Clock
8
No Connection