Hello, I am trying to troubleshoot a monitor (Westinghouse LCM-22w2) for my sister in law and having some trouble doing so. She tells me the monitor works sometimes, but sometimes she gets a No Signal Message on the computer. She hooked up her old monitor and no problems with signals. So that rules out the source being the problem. So I take the monitor home to see what I can do, I use my X-Box 360 with the VGA peripheral to troubleshoot as I know the signal is good. I turn on the monitor and it works fine. I use the monitor for some Halo online play, it works fine. So I shut it off and go to bed. I wake up to see if it works and does not. I check all the connections, they are good to go. I have audio as well, so the xbox is working. What could cause the monitor to work at times and not at other times?