Mac OS 7.6 and Passive Matrix PowerBook Display Issue (1/97)


Sometimes on the restart after installing Mac OS 7.6, or more often after resetting PRAM, the contrast of my PowerBook passive matrix display is very dark. The brightness and contrast controls do not let the screen be adjusted to a more usable level. Is there a workaround?


Here is a workaround. Restart the PowerBook; after it has fully started press and hold the power button to get the shutdown dialog, then press the "R" key to restart the computer. On startup, the display should be functioning normally, or allow adjustment if you changed the brightness and contrast settings while the display was dark.

Engineering is aware of this issue, and they are working to correct it in a future update.

Affected PowerBook computers
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This issue has been duplicated on PowerBook 5300/190 computers only, but may occur on other passive matrix equipped PowerBook computers. It has not been duplicated on the PowerBook 1400cs computer.

This information can also be found in the About Mac OS 7.6 Read Me file.


Published Date: Feb 18, 2012