MSI PRO B550-P GEN3 Manuel D'utilisation page 33

CPU_PWR1, ATX_PWR1: Power Connectors
These connectors allow you to connect an ATX power supply.
CPU_PWR1
8
4
12
ATX_PWR1
1
⚠
Important
Make sure that all the power cables are securely connected to a proper ATX power
supply to ensure stable operation of the motherboard.
CPU_PWR1
Pin
1
3
5
7
ATX_PWR1
Pin
1
5
1
3
5
24
7
9
11
13
13
15
17
19
21
23
31
Signal Name Pin
Ground 2
Ground 4
+12V 6
+12V 8
Signal Name Pin
+3.3V 2
Ground 4
Ground 6
Ground 8
5VSB 10
+12V 12
+3.3V 14
Ground 16
Ground 18
Ground 20
+5V 22
+5V 24
Signal Name
Ground
Ground
+12V
+12V
Signal Name
+3.3V
+5V
+5V
PWR OK
+12V
+3.3V
-12V
PS-ON#
Ground
Res
+5V
Ground