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Jumpers, Switches, and Connectors

Dell™ PowerEdge™ 850 Systems Installation and Troubleshooting Guide

  Jumpers—A General Explanation

  System Board Jumpers

  System Board Connectors

  Riser Card 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 with a triangle so that you can identify each pin number based on the location of pin 1.

Figure A-2 shows the location and default settings of the server-module jumper blocks. See Table A-1 for the designations, default settings, and functions of the jumpers.


System Board Jumpers

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

Figure A-2. System Board Jumpers

Table A-1. System Board Jumper Settings 

Jumper

Setting

Description

PASSWD_EN

  (default)

The password feature is enabled.

The password feature is disabled.

NVRAM_CLR

  (default)

The configuration settings in NVRAM are retained at system boot.

The configuration settings in NVRAM are cleared at next system boot.

 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

12V

power supply connector

BATTERY

Connector for the 3.0 V coin battery

DAUGHTER_CONN1

Connector for the daughter card

DIMMn_ x

Memory modules (4)

FAN

Power connector for the fans

FRONT_PANEL

Control panel interface connector

INTRUSION_SWITCH

Connector for the chassis intrusion switch

PRI_IDE1

Optical drive interface connector

PROC

Processor socket

PWR_CONN

power supply connector

RISER_CONN1

Riser card interface connector

SATA_PORT_n

Connectors for the SATA hard drives

USB_CONN

Control panel interface connector


Riser Card Connectors

The system is available with either a PCIe riser card or a PCI-X/PCIe riser card. See Figure A-4 and Figure A-5 for the location and description of the expansion-card slots on the two riser cards.

Figure A-4. PCIe Riser Card Connectors

Figure A-5. PCI-X/PCIe Riser Card Connectors


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: Only trained service technicians are authorized to remove the system cover and access any of the components inside the system. Before performing any procedure, see your Product 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. Remove the password jumper plug.

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 install the jumper plug.

NOTE: If you assign a new system and/or setup password with the jumper plug still removed, 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. Install the password jumper plug.

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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