Acer Aspire X3990 Acer Aspire X3990 Desktop Service Guide - Page 86

Jumper Setting The section explains how to set jumper for correct configuration of the mainboard. Setting Jumper Use the motherboard jumpers to set system configuration options. Jumpers with more Than one pin are numbered. When setting the jumpers, ensure that the jumper caps are Placed on the correct pins. The illustrations show a 2-pin jumper. Whenthe jumper cap is placed on both pins, thejumper is SHORT. If you remove the jumpercap, or place the jumper cap on just one pin,the jumper is OPEN. This illustration shows a 3-pin jumper. Pins1 and 2 are SHORT. Checking Jumper Settings The following illustration shows the location of the motherboard jumpers. Pin 1 is labeled. Chapter 5 78