Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have a macbookpro unibody late 2008 15p and use OS X Lion, 10.7.3. I use always an external monitor and close the lid. When I finish my work day I put the macbook in sleep mode and it switches off. The next day I want to switch on my mac so the previous state appears on screen (in my external monitor). But 20% of the times it happens that external monitor screen is black, and if I open the lid, macbook screen is also black, but the laptop is switched on. It seems that for some reason the screen output does not work. Since I do not want to lose all my open windows and documents I try to put it again in sleep mode and reboot, but the combination cmd+alt+eject and others do not work here and the macbook remains switched on.

I already tried resetting PRAM and other similar things.

So at this point I would like to know whether this can be solved.

share|improve this question

I have a similar issue (albeit without the external screen) where I can get the screen to come alive by using the brightness button (F2).

share|improve this answer
yes, I also tried that, but does not work for me – flow May 21 '12 at 7:10

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.