I have a Sony VAIO PCG-3112L running Windows 7. It worked fine on one monitor, but now I'm using it with a 2 year old LG Flatron W2252TQ-TF. The colors are sorta off (although that might just be the monitor), but more annoyingly there are many horizontal flickering lines. It's more noticeable on non-white backgrounds.
I tried rebooting the monitor, and reseting it to factory settings, but that didn't solve the issue.
What could be the cause of this? The monitor works fine with an Asus netbook. I have checked that both ends of the VGA cable are plugged in between the Vaio and the monitor.
Update: I tried with a Sceptre TV, and experienced the same issue. (The Asus with the same cable was fine for that TV.)
Update 2: Sometimes, using the same configuration described above with the LG monitor, the problem does not occur. I am not sure what causes this.