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Jumpers, Switches, and Connectors

Dell™ PowerEdge™ 400SC Systems Installation and Troubleshooting Guide

  Jumpers—A General Explanation

  System Board Jumpers

  System Board Connectors

  Disabling a Forgotten Password


This section provides specific information about the system jumpers. It also provides some basic information on jumpers and switches and describes the connectors on the various boards in the system.

Jumpers—A General Explanation

Jumpers provide a convenient and reversible way of reconfiguring the circuitry on a printed circuit board. When reconfiguring the system, you may need to change jumper settings on circuit boards or drives.

Jumpers

Jumpers are small blocks on a circuit board with two or more pins emerging from them. Plastic plugs containing a wire fit down over the pins. The wire connects the pins and creates a circuit. To change a jumper setting, pull the plug off its pin(s) and carefully fit it down onto the pin(s) indicated. Figure A-1 shows an example of a jumper.

Figure A-1. Example Jumper

A jumper is referred to as open or unjumpered when the plug is pushed down over only one pin or if there is no plug at all. When the plug is pushed down over two pins, the jumper is referred to as jumpered. The jumper setting is often shown in text as two numbers, such as 1–2. The number 1 is printed on the circuit board so that you can identify each pin number based on the location of pin 1.

System Board Jumpers

Figure A-2 shows the location of the configuration jumpers on the system board. Table A-1 lists the jumpers settings.

Figure A-2. System Board Jumpers

Table A-1. System Board Jumper Settings 

Jumper

Setting

Description

J8H4

(default)

Password features are enabled.


Password features are disabled.

 jumpered      unjumpered

System Board Connectors

See Figure A-3 and Table A-2 for the location and description of the system board connectors.

Figure A-3. System Board Connectors

Table A-2. System Board Connectors 

Connector

Description

AGP

AGP video card (not supported)

BATTERY

System battery

CD_IN

CD/DVD audio

CHANNEL_x DIMMn

Memory module connectors

CPU_0

Processor

fan

Power connector for the processor cooling shroud fan

FDD

Diskette drive

FRONT_FAN

Front system fan power (not supported)

FRONT_PANEL

Front-panel switches and indicators

PCI1–4

PCI expansion-card slots (If you install a video card, it must be installed in slot 1.)

PRI_IDE

Primary IDE

PWR

System board power

REAR _FAN

Back system fan power (not supported)

SATA_n

Primary and secondary SATA drives (when available)

SEC_IDE

Secondary IDE

12V_PWR

System board power

NOTE: For the full name of an abbreviation or acronym used in this table, see "Abbreviations and Acronyms."

Disabling a Forgotten Password

The system's software security features include a system password and a setup password, which are discussed in detail in "Using the System Setup Program" in your User's Guide. The password jumper enables these password features or disables them and clears any password(s) currently in use.

CAUTION: See your System Information Guide for complete information about safety precautions, working inside the computer, and protecting against electrostatic discharge.
  1. Turn off the system and attached peripherals, and disconnect the system from the electrical outlet.

  2. Open the system. See "Opening the System" in "Troubleshooting Your System."

  3. Move the password jumper plug to disable the password feature.

See Figure A-2 to locate the password jumper on the system board.

  1. Close the system. See "Closing the System" in "Troubleshooting Your System."

  2. Reconnect the system to the electrical outlet, and turn on the system.

The existing passwords are not disabled (erased) until the system boots with the password jumper plug removed. However, before you assign a new system and/or setup password, you must move the jumper plug to enable the password feature.

NOTE: If you assign a new system and/or setup password with the jumper plug still set to the disabled position, the system disables the new password(s) the next time it boots.
  1. Turn off the system, including any attached peripherals, and disconnect the system from the electrical outlet.

  2. Open the system.

  3. Reinstall the password jumper plug to enable the password feature.

See Figure A-2 to locate the password jumper on the system board.

  1. Close the system, reconnect the system to the electrical outlet, and turn on the system.

  2. Assign a new system and/or setup password.

To assign a new password using the System Setup program, see "Using the System Setup Program" in your User's Guide.

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