Asus AT3GC-I User Manual - Page 20

6. 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 fit these connectors in only one orientation. Find the proper orientation and push down firmly until the connectors completely fit. ATX12V EATXPWR GND GND +3 Volts PIN 1 +12 Volts +12 Volts +5V Standby +12V DC +12V DC Power OK GND +5 Volts GND +5 Volts GND +3 Volts +3 Volts PIN 1 AT3GC-I AT3GC-I ATX power connectors GND +5 Volts +5 Volts +5 Volts -5 Volts GND GND GND PSON# GND -12 Volts +3 Volts • 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. • If you intend to use a PSU with 20-pin and 4-pin power plugs, make sure 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 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. 7. Speaker connector (4- pin SPEAKER) This 4-pin connector is for the chassis-mounted system warning speaker. The speaker allows you to hear system beeps and warnings. SPEAKER AT3GC-I +5V GND GND Speaker Out PIN 1 AT3GC-I Speaker Out Connector 1-11 Chapter 1: Product introduction