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What should I do when Ubuntu freezes?
Since I installed Ubuntu 12.04 it keeps on freezing. It happens on different PCs and I don't think it's a memory problem. For example, I recently got a laptoptop with 8Gb of RAM and I got the problem there as well. The only solution is unplugging the machine or pressing +REISUB (I found this magic spell in a related thread).
The problem seems to be triggered by a task switch, e.g. when I press F12, which moves guake to the background or into the foreground or when I press ALT+TAB, which switches the current gui task.
I am suspecting guake, Chrome, or Evince are possible causes of the problem. However, I disabled guake on the laptop and I've seen the problem once since then.
I just reinstalled 12.10 and I had 3 freezes in 10 minutes. I wasn't doing anything special. The only thing I was doing was running Chrome and gimp.