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Chapter 4: Motherboard Connections
4.2 Headers and Connectors
Fan Headers
There are six 4-pin fan headers on the motherboard. Although these are 4-pin fan headers,
pins 1-3 are backward compatible with traditional 3-pin fans. The onboard fan speeds are
controlled by Thermal Management (via Hardware Monitoring) in the BIOS. The fan speed
is controlled by the BMC.
Fan Header
Pin Definitions
Pin#
Definition
1
Ground (Black)
2
+12V (Red)
3
Tachometer
4
PWM Control
4-pin 12V Power for GPU
JPWR1 is a 4-pin 12V power connector for a GPU card that requires an extra 12V of power,
up to 75W.
Extended CMOS Battery
J18 is a 2-pin connector for an external CMOS battery. Refer to Chapter 3 for battery
installation instructions. This connector is also used to clear the CMOS. To clear the CMOS,
remove the battery, shorts pins 1-2 for more than 10 seconds and then install the battery.
TPM Header
The JTPM1 header is used to connect a Trusted Platform Module (TPM)/Port 80, which is
available from a third-party vendor. A TPM/Port 80 connector is a security device that supports
encryption and authentication in hard drives. It allows the motherboard to deny access if the
TPM associated with the hard drive is not installed in the system.
Trusted Platform Module Header
Pin Definitions
Pin#
Definition
Pin#
Definition
1
LCLK
2
GND1
3
LFRAME#
4
No Pin
5
LRESET#
6
+5V/NC
7
LAD3
8
LAD2
9
+3.3V
10
LAD1
11
LAD0
12
GND2
13
SMB_CLK
14
SMB_DAT
15
+3.3V_DUAL
16
SERIRQ
17
GND3
18
CLKRUN#/NC
19
LPCPD#
20
LDRQ# (X)
