After period of inactivity screen went dim, and eventually got black, it couldn't get to previous state. When mouse is moved screen from black came to minimum brightness state. Combination of Fn and brightness button fixed this, but on very strange way. Every time I pressed button to increase brightness it came more bright but with next push of button went to minimal brightness. So, every second push of button puts screen to minimum. Gremlins?
closed as off topic by fossfreedom♦ May 14 '12 at 9:20
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