Owner's manual
4. ATX power connectors (24-pin EATXPWR, 4-pin ATX12V)
These connectors are for an ATX power supply. The plugs from the power supply are
designed to t these connectors in only one orientation. Find the proper orientation and
push down rmly until the connectors completely t.
M3N78-AM
M3N78-AM ATX power connectors
EATXPWR
PIN 1
GND
+5 Volts
+5 Volts
+5 Volts
-5 Volts
GND
GND
GND
PSON#
GND
-12 Volts
+3 Volts
+3 Volts
+12 Volts
+12 Volts
+5V Standby
Power OK
GND
+5 Volts
GND
+5 Volts
GND
+3 Volts
+3 Volts
ATX12V
PIN 1
+12V DC
+12V DC
GND
GND
•
We recommend that you use an ATX 12 V Specication 2.0-compliant power supply
unit (PSU) with a minimum of 300 W power rating. This PSU type has 24-pin and 4-pin
power plugs.
•
If you intend to use a PSU with 20-pin and 4-pin power plugs, ensure that the 20-pin
power plug can provide at least 15 A on +12 V and that the PSU has a minimum power
rating of 300 W. The system may become unstable or may not boot up if the power is
inadequate.
•
Do not forget to connect the 4-pin ATX +12 V power plug. Otherwise, the system will not
boot up.
• We recommend that you use a PSU with higher power output when conguring a
system with more power-consuming devices or when you intend to install additional
devices. The system may become unstable or may not boot up if the power is
inadequate.
•
If you are uncertain about the minimum power supply requirement for your system,
refer to the Recommended Power Supply Wattage Calculator at http://support.asus.
com/PowerSupplyCalculator/PSCalculator.aspx?SLanguage=en-us for details.
5. Optical drive audio in connector (4-pin CD)
This connector allows you to receive stereo audio input from sound sources such as a
CD-ROM, TV tuner, or MPEG card.
CD
Right Audio Channel
GND
GND
Left Audio Channel
M3N78-AM
M3N78-AM Internal audio connector
Chapter 1: Product introduction 1-21