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I have a Samsung SyncMaster P2470HN monitor and every time I plug it in and set it for use it starts to blink intermittently every 2 seconds. First it show the workspace, then it blinks and shows the message "Check signal cable", then it show the workspace again and it goes on forever (until I unplug it). Now I'm using 32 bits Lubuntu 12.04, but I used to have the same problem while on 32 bits Ubuntu 12.04.

My video card configuration:
00:02.0 VGA compatible controller: Intel Corporation Mobile 945GM/GMS, 943/940GML Express Integrated Graphics Controller (rev 03)


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Does it do that while you are booting into Ubuntu or after you have booted into Ubuntu? If it does that right from when you start up your system, chances are, it is not Ubuntu related. Does the same problem occur when the monitor is connected to a mac or windows system? If so, this is not the right place for your question. If you think it is related to Ubuntu, please specify HOW you connect your monitor: HDMI, VGA or DVI –  matv1 Feb 4 '13 at 2:31
First, it happens anytime I connect the monitor. Second, it doesn't happen when connected to Windows. Third, I connect it throw VGA (I thought it was clear through the video card config. My mistake, sorry =D). Thanks. –  infostacker Feb 4 '13 at 13:47
Ok. I have a similar Monitor. Sounds to me like the monitor is confused about what kind of connection it is using. Maybe all your settings are configured to 'automatic detect'. I looked around in my monitor menu and there are a few places where you can configure your settings manualy. I would try that. So manualy set VGA input. ALso: If you have a choice between AV and PC mode, then go for PC mode. This seems to have been an issue in Ubuntu using some Samsung monitors that caused flickering. Gd Luck and let us know. –  matv1 Feb 4 '13 at 19:18
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