Question : Problem: Samsung HDTV used as a 2nd monitor cuts off

I have a 24" Samsung LN-82738D HDTV that I have been using as a PC monitor for the past 3 months. The HDTV is 2 years old. The monitor has been working perfectly until a couple of days ago when it suddenly cut off for no apparent reason. I turned the monitor off, then back on and it again functioned normally for another few hours. But then it cut out again. There does not seem to be a consistent time frame before the monitor cuts off, but it will operate anywhere from a couple of hours to 10 minutes before it once again cuts off. The frequency with which this is occurring is increasing. I was convinced that this was a sign of the monitor beginning to fail until I unplugged the VGA cable to the monitor. When I did that, the monitor immediately lit up with a "no PC signal" error message.

Is it possible for one channel of a video card to begin to fail intermittently? Or is the likely cause in the monitor itself? Is there any way I can verify the source of the failure without having to swap out monitors or video cards?

Thanks in advance for any help you can offer.

Answer : Problem: Samsung HDTV used as a 2nd monitor cuts off

Just throwing out some ideas here - you havent happened to have updated video card drivers in the last couple of days have you? Does your computer have a built on vga port on the motherboard and then an addin card that provides DVI? Might be worth an effort to switch to your built on video adapater and run it for several hours so you could narrow it down to a video card or monitor problem.