This is problem with the Slot Manager. However it was only discovered when Power Macintosh computers were running System 7.5 and virtual memory. It has also been found to occur with RAM Doubler installed. This problem is corrected in System Update 7.5.
Until you get the update, three work arounds for this problem.
1) Turn off virtual memory
2) Open and close the Monitors control panel.
a) Go to the Monitors control panel.
b) Click Options. A dialog appears with the message "No Board Info".
c) Click "OK".
d) Close the control panel.
e) SHUT DOWN (restarting doesn't correct this).
When the computer restarts, everything comes up in black and White
so you have go back into the Monitors control panel and reset
the number of colors.
3) Do a forced restart (command-control-power).
These articles can help you locate software updates mentioned here:
* Where To Find Apple Software Updates
Lists online services for "free" Apple software updates
* Obtaining Apple Product Support in the USA
Lists 800 numbers and online services for software updates, Apple
support information, and a subset of the Apple Tech. Info. Library
Article Change History:
21 Sep 1995 - Corrected minor typo.
08 May 1995 - Added keywords kppc and sys75.
15 Mar 1995 - Added System Update 7.5 information.
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