The following figure shows the location of the jumpers on the system board.
System Board Jumpers
NOTICE: Before changing a jumper setting, verify that the standby power
light on the system board has turned off. Otherwise, damage to your computer
or unpredictable results may occur. To locate this light, see "System Board
Components" or the interior service label.
To change a jumper setting, pull the plug off its pin(s) and carefully fit it
down onto the pin(s) indicated.
The following table lists the system board jumpers and their settings.
*Offers subject to change. Taxes, shipping, handling and other fees apply. U.S. Dell Small Business new purchases only. LIMIT 5 DISCOUNTED OR PROMOTIONAL ITEMS PER CUSTOMER. LIMIT 5 VOSTRO OR INSPIRON UNITS PER CUSTOMER. Dell reserves right to cancel orders arising from pricing or other errors.
(default)
jumpered 
unjumpered