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Chapter 3: Motherboard Connections
Chapter 3
Motherboard Connections
This section describes the connections on the motherboard and provides pinout definitions.
Note that depending on how the system is configured, not all connections are required.
The LEDs on the motherboard are also described here. A motherboard layout indicating
component locations may be found in Chapter 1.
Please review the Safety Precautions in Chapter 3 before installing or removing components.
3.1 Power Connections
Two power connections supply the motherboard and several more supply for onboard devices.
Main ATX Power Supply Connector
The primary power supply connector (JPWR2) meets the ATX SSI EPS 24-pin specification.
You must also connect the 8-pin (JPWR1) processor power connector to your power supply.
ATX Power 24-pin Connector
Pin Definitions
Pin#
Definition
Pin#
Definition
13
+3.3V
1
+3.3V
14
-12V
2
+3.3V
15
GND
3
GND
16
PS_ON
4
+5V
17
GND
5
GND
18
GND
6
+5V
19
GND
7
GND
20
Res (NC)
8
PWR_OK
21
+5V
9
5VSB
22
+5V
10
+12V
23
+5V
11
+12V
24
GND
12
+3.3V
Secondary Power Connector
JPWR1 must also be connected to the power supply. This connector is used to power the
processor.
+12V 8-pin Power
Pin Definitions
Pin#
Definition
1 - 4 GND
5 - 8 +12V
Required Connection
