This problem is peculiar to the Macintosh IIfx with 4MB of RAM installed. Apple states that, when using only 4MB of RAM in the Macintosh IIfx, the SIMMs MUST BE installed in bank A. Although the Macintosh IIfx may work normally in some configurations with the SIMMs installed in bank B; in others, it doesn't.
To eliminate the problems you are experiencing with the Macintosh IIfx, make sure the RAM SIMMs are in bank A.
Article Change History:
08 Nov 1994 - Reviewed for technical accuracy.
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