HP 330 Service Information Manual page 97

3. Turn the computer off and change the processor and 4 Mbyte RAM controller board's
switches to the configuration that had the fastest time.
Doing this relocates the processor board RAM to the second 4 Mbyte block (FFB) whose
top address is 1111111110 as shown in Table 3-5, Example 2. The 4 Mbyte block of
RAM previously occupying these addresses moves up to the top of RAM, 1111111111
(FFF).
Note
Should an error be made in configuring memory, error messages may
be displayed during power-up. Check the configuration switches on all
RAM assemblies and the Model 330 processor board carefully.
Functional Description
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