7 Replies Latest reply: Feb 21, 2012 9:22 AM by ChazThePhoenix
petedragon Level 1 Level 1 (0 points)

I have a mid-2011 Thunderbolt 21.5" iMac. A secondary monitor is connected to the iMac with a Mini DisplayPort-to-HDMI cable (a single cable, not an adaptor and cable).


When I was running Snow Leopard, the monitor worked just fine. After upgrading to Lion, the second monitor just has a black screen, and quickly goes into power save mode.


I have already tried resetting the NVRAM (as described here: http://support.apple.com/kb/HT1379) and resetting the SMC (as described here: http://support.apple.com/kb/HT3964).


Has anyone seen this problem? Any other suggestions for solutions?

iMac, Mac OS X (10.7)