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DIN-DIN

Level 1 (0 points)

Q: Dual Display on OSX Mountain Lion not working

Ever Since I have upgraded my 2011 iMac, it has not been detecting my other monitor in the display settings. Any way to fix this?

iMac

Posted on Aug 6, 2012 8:21 PM

I have this question too

Q: Dual Display on OSX Mountain Lion not working

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by nab004,

nab004 Aug 11, 2012 10:45 PM in response to DIN-DIN
Level 1 (0 points)

Aug 11, 2012 10:45 PM in response to DIN-DIN

Press option when in the displays System Preference pane. A little "Detect Displays" button should pop up in the lower right. Really wish they hadn't hidden this.
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by DIN-DIN,

DIN-DIN Aug 11, 2012 11:49 PM in response to nab004
Level 1 (0 points)

Aug 11, 2012 11:49 PM in response to nab004

I tried holding down option, but then nothing happens when I click "Detect Display" :[
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by quicksilver8,

quicksilver8 Aug 11, 2012 11:57 PM in response to DIN-DIN
Level 2 (315 points)

Aug 11, 2012 11:57 PM in response to DIN-DIN

http://support.apple.com/kb/HT1573
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by DIN-DIN,

DIN-DIN Aug 12, 2012 1:24 AM in response to quicksilver8
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Aug 12, 2012 1:24 AM in response to quicksilver8

Nothing has been working :[ I hope they fix this soon with an update
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by dlivdahl,

dlivdahl Aug 23, 2012 7:45 AM in response to DIN-DIN
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Aug 23, 2012 7:45 AM in response to DIN-DIN

I have a similar problem. I have two DELL U2410 displays (NVIDIA GeForce 9400M 256 MB graphics) connected to my Macbook Pro using a Diamond dual monitor adapter and they both worked fine with Lion but now only one of them is detected after upgrading to Mountain Lion. I tried resetting the PRAM but that did not change anything. Checked cables, everything else appears normal.
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by GIC1969,

GIC1969 Oct 4, 2012 10:10 AM in response to DIN-DIN
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Oct 4, 2012 10:10 AM in response to DIN-DIN

I have had the same problem since upgrading. To get it to work, every day I have to unplug the Thunderbolt cable and plug it back in.
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