B-2 System Board Jumpers
CHANGING PROCESSOR JUMPER SETTINGS
Use the following procedure when replacing the installed processor with a faster speed
processor. Jumpers requiring setting changes include the Processor/Bus Speed and ATCLK
jumpers.
1.
Turn off and unplug the system and any connected external options.
WARNING:
System power must be off before
removing the cover and changing a jumper
setting.
2.
Remove the system unit cover (see Section 3, Option Installation, for cover
removal).
3.
Replace the processor (see Section 3 for processor upgrade procedures).
4.
Remove any expansion boards blocking access to the jumpers.
5.
Locate the Processor/Bus Speed, ATCLK, and Processor Voltage jumper blocks
on the system board (see Figure Appendix B-1).
6.
Set the Processor/Bus Speed and ATCLK jumpers per Figure Appendix B-2.
7.
Set the Processor Voltage jumper (see Figure Appendix B-2) on the system
board as follows:
n
For the 150-MHz processor (60-MHz clock speed), set the jumper on the VR
block (3.38 volts)
n
For the 166-MHz processor (66-MHz clock speed), set the jumper on the
VRE block (3.52 volts)
CAUTION:
Unless updating the processor to a
faster speed, leave the Processor Voltage jumper
and Bus/Core jumper at the factory setting.
Changing the Voltage and Bus/Core jumpers
could damage the processor.
8.
Reinstall any removed expansion boards.
9.
Reinstall the system cover.
10.
Reconnect any disconnected peripherals and turn on the system.
