Manual

support.dell.com Jumpers, Switches, and Connectors A-1
APPENDIX A
Jumpers, Switches, and
Connectors
This section provides specific information about the jumpers on the system board. It
also provides some basic information on jumpers and switches and describes the
connectors and sockets on the various boards in the system.
Jumpers and Switches—A General
Explanation
Jumpers and switches 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 the system board. You may also need to change jumper
and/or switch settings on expansion cards 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.
NOTICE: Make sure the system is turned off before you change a jumper
setting. Otherwise, damage to the system or unpredictable results may
occur.
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,
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