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Appendix I Replacing SIMMs
Model 281xSA dynamic random access memory (DRAM) can be upgraded
from the default 2-megabyte (MB) configuration to a total of 8 MB. The
DRAM consists of a single in-line memory module (SIMM) that is installed in
a SIMM socket on a printed circuit board inside the hub.
This appendix outlines the procedures for replacing a SIMM in the Model
281xSA hub. This appendix includes the following information and
procedures:
■
Preparing for the installation procedure
■
Removing the cover of the hub
■
Replacing a SIMM
■
Setting the DRAM configuration jumpers
■
Reinstalling the cover
■
Verifying installation
CAUTION:
System 2000 equipment uses electronic components that are
sensitive to static electricity. Static discharge from your clothing or other
fixtures around you can damage these components. You should take all
possible precautions to prevent static discharge damage when working with
printed circuit boards.
If possible, place all printed circuit boards on an antistatic mat until you are
ready to install them. If you do not have an antistatic mat, wear a discharge
leash to free yourself of static before touching any of the printed circuit
boards, or free yourself of static by touching the metal of the chassis before
handling a module.