2.ATX power connectors (24-pin EATXPWR, 4-pin ATX12V)

These connectors are for ATX power supply plugs. The power supply plugs are designed to fit these connectors in only one orientation. Find the proper orientation and push down firmly until the connectors completely fit.

ATX12V EATXPWR

B75M-A

 

 

DC DC

+3

Volts

 

 

+12V +12V

 

 

+12

Volts

 

 

 

 

+12

Volts

 

 

 

 

+5V Standby

 

 

 

 

 

Power OK

 

 

 

 

PIN 1

GND

 

 

GND GND

+5

Volts

 

 

 

 

GND

 

 

 

 

 

 

 

 

+5

Volts

 

 

 

 

 

 

GND

 

 

 

 

 

 

 

 

 

 

 

+3

Volts

 

 

 

 

 

 

 

 

 

 

 

 

 

 

+3

Volts

 

 

 

 

PIN 1

GND

+5 Volts

+5 Volts

+5 Volts

-5 Volts

GND

GND

GND

PSON#

GND

-12 Volts

+3 Volts

B75M-A ATX power connectors

•We recommend that you use an ATX 12V Specification 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.

•DO NOT forget to connect the 4-pin ATX +12V power plug. Otherwise, the system will not boot up.

•We recommend that you use a PSU with higher power output when configuring 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.

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Chapter 1: Product introduction