Acer Aspire G7750 Service Guide - Page 93

Power Connectors The ATX 24-pin power connector (JPWR1) allows you to connect an ATX 24-pin or ATX 20-pin power supply. When using a 20-pin ATX power supply, plug the power supply along with pins 1 and 13. A foolproof design is on pins 11, 12, 23, and 24 to avoid wrong installation. Pin Signal 1 +3.3V 2 +3.3V 3 GND 4 +5V 5 GND 6 +5V 7 GND 8 PWR OK 9 5VSB 10 +12V 11 +12V 12 +3.3V Pin Signal 13 +3.3V 14 -12V 15 GND 16 PS-ON# 17 GND 18 GND 19 GND 20 Res 21 +5V 22 +5V 23 +5V 24 GND The ATX 12V power connector (JPWR2) provides power to the processor. Pin Signal 1 GND 2 GND 3 GND 4 GND Pin Signal 5 +12V 6 +12V 7 +12V 8 +12V Important notification about power issue The NForce chipset is very sensitive to ESD (Electrostatic Discharge), therefore this issue mostly happens while the users intensively swap memory modules under S5 (power-off) states, and the power cord is plugged while installing modules. Due to several pins are very sensitive to ESD, so this kind of memory-replacement actions might cause system chipset unable to boot. Please follow the following solution to avoid this situation. 1. Unplug the AC power cable. 2. Unplug the ATX 24-pin and ATX 12V power connectors before the first installation or during system upgrade procedure. Chapter 5 85