2. 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.
•
We recommend that you use an ATX 12V Specication 2.0-compliant power supply unit
(PSU) with a minimum of 300W 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 300W. The system may become unstable or may not boot up if the power is
inadequate.
•
DO NOT forget to connect the 4-pin ATX12V 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.
M5A78L-M LX
M5A78L-M LX 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
Chapter 1: Product introduction1-22