Owner's Manual
A75MH / A55MH 
11 
ATXPWR1: AT X Power Source Connector 
This connector allows user to connect 24-pin power connector on the ATX 
power supply. 
1
12
13
24
Pin Assignment  Pin Assignment 
13 +3.3V  1 +3.3V 
14 -12V  2 +3.3V 
15 Ground  3 Ground 
16 PS_ON  4 +5V 
17 Ground  5 Ground 
18 Ground  6 +5V 
19 Ground  7 Ground 
20 NC  8 PW_OK 
21 +5V  9 Standby Voltage+5V 
22 +5V  10 +12V 
23 +5V  11 +12V 
24 Ground  12 +3.3V 
Note: 
Before you power on the system, please make sure that both ATXPWR1 and ATXPWR2 
connectors have been plugged-in. 
PCI1: Peripheral Component Interconnect Slot 
This motherboard is equipped with 1 standard PCI slot. PCI stands for Peripheral 
Component Interconnect, and it is a bus standard for expansion cards.  
PCI1










