Supermicro H8DGU-LN4F+, User Manual

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Chapter 2: Installation
2-21
2-8 Jumper Settings
Explanation of Jumpers
To modify the operation of the
motherboard, jumpers can be used
to choose between optional settings.
Jumpers create shorts between two
pins to change the function of the
connector. Pin 1 is identifi ed with a
square solder pad on the printed circuit
board. See the diagram at right for
an example of jumping pins 1 and 2.
Refer to the motherboard layout page
for jumper locations.
Note: On two-pin jumpers, "Closed"
means the jumper is on and "Open"
means the jumper is off the pins.
Connector
Pins
Jumper
Setting
3 2 1
3 2 1
CMOS Clear
JBT1 is used to clear CMOS, which will also clear any passwords. Instead of pins,
this jumper consists of contact pads to prevent accidentally clearing the contents
of CMOS.
To Clear CMOS
1. First power down the system and unplug the power cord(s). It is also
recommended that you remove the onboard battery from the serverboard.
2. With the power disconnected, short the CMOS pads with a metal object such
as a small screwdriver.
3. Remove the screwdriver (or shorting device).
4. Reconnect the power cord(s) and power on the system.
Note 1. For an ATX power supply, you must completely shut down the system,
remove the AC power cord, and then short JBT1 to clear CMOS.
Note 2. Be sure to remove the onboard CMOS Battery before you short JBT1 to
clear CMOS.
Note 3. Clearing CMOS will also clear all passwords.
Note 4: Do not use the PW_ON connector to clear CMOS.
JBT1 contact pads