Plz no tpe lik dis or no anser!!
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There is an open bug regarding external monitors and users of intel graphics. I have a Sandy Bridge processor and I have to be very careful how I plug things in.
If I plug in my USB Hub, External Monitor, etc and then boot the computer, LightDM comes up as expected and then Unity / Gnome Shell goes into a hard freeze upon log-in.
I was intrigued that LightDM worked correctly. So, I tried various window managers and eventually discovered that xfwm from XFCE4 / Xubuntu works just fine and does not trigger this bug. Alternatively, I am able to avoid it by first connecting the external monitor, logging in to Unity and THEN inserting my USB hub with external keyboard, mouse, printer, etc. A small hassle, but everything seems stable.
This problem drove me nuts because I loves my external monitor. Hope it helps someone else. I'm using a Lenovo X220 laptop. I don't know if desktop users are affected by this. YMMV.
Last edited by gunksta; May 3rd, 2012 at 06:14 PM. Reason: Noted that I'm talking about a laptop.
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