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IRockedAmadeus · Oct 22, 2006, 11:31 AM

I called Apple about problems with my Macbook turning itself on, and their advice was to reset the PMU and PRAM. That fixed the powering on problem, but started a new annoyance. I usually keep the brightness of the screen at or below halfway. Now whenever I turn on my Macbook it forgets the brightness setting and comes on at full brightness. I have all of the firmware/ OS X updates installed. Thanks in advance for any help.

indigoimac · Oct 23, 2006, 08:05 PM

Have you tried repairing permissions from Disk Utility?

Also try downloading a program called OnyX, go under maintence and run the day/week/month scripts, then do a full/complete system optimize, maybe some preference got screwed up.

And you may also want to try a prog called Preferential Treatment to see if it is some sort of corrupted pref.
Preferential Treatment 1.1.6 - MacUpdate

And if all else fails, zero-out the drive and do a clean unarchived reinstall.

Just a couple of ideas.

ginoledesma · Oct 23, 2006, 10:23 PM

I have the same problem, although I can get mine to replicate this "bug" when I plug or unplug an external monitor. Haven't bothered with resetting the PMU yet, but repairing disk permissions hasn't done anything for me.

IRockedAmadeus · Oct 24, 2006, 08:50 PM

I finally took my Macbook to the Apple store to get to the bottom of this. The associate was unsure of the cause, but suggested it was software related, probably due to an update. I completely zeroed (erased) the drive and reinstalled OS X, and that did the trick. Even after updating to 10.4.8 my Macbook remembers the brightness when resetting.