Digital Equipment VAXstation 4000 90, Service Information

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Module Removal,
Continued
Light and
Switches
Module
Replacement To replace the light and switches module, perform the following
steps:
Step Action
1 Align the switches with their respective holes in the front
bezel.
2 Align the connector on the lower side of the module
with the connector on the system module and seat the
connector.
Memory
Module
Identification Three types of memory modules are available: 4 MB (MS44-
AA), 4 MB reduced cost (MS44L), and 16 MB (MS44-CA). The
VAXstation 4000 Model 90 can use any of the three memory
modules. Memory modules must be installed in sets of four 4-MB
modules, or four 16-MB modules.
Ensure that you have the correct memory module before
installation. To identify a memory module, locate the etch on
the left side of the memory module. The 4-MB modules have AA
or AL on the etch board, and the 16-MB modules have CA on the
etch board. Figure 6–10 shows the location of the memory module
ID number.
When installing four 4-MB memory modules and four 16-MB
memory modules, the 4-MB memory modules must be installed in
memory locations 0A, 0B, 0C, 0D.
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