Ubuntu 12.10: Intel – Dealing with the Suspend Bug

Intel users often run into an annoying bug: When you shut the laptop cover, the machine falls into a light sleep, from which it should theoretically awaken as soon as you open the cover again. However, some computers, especially those with Intel graphics, will hiccup, resulting in a black or frozen screen. This problem is well known to developers [1].

You don't necessarily need to restart the computer to fix the problem. Often it's enough to switch to a virtual terminal (VT) and give the LightDM display manager a nudge. Unfortunately, doing so clears the current desktop session of all open windows. To access VT, press Ctrl+Alt+F1, which takes you to a black-and-white screen with a login prompt. On some keyboards, you also need to press the Fn (function) key to get to the F1 key. Next, you can log in with your user credentials and enter the following to reanimate the display manager:

$ sudo service lightdm restart

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