I have had this Sony Trinitron 19in G400 Monitor for over 4 years now and have love it. I never had any problems until now. I am well aware of the 2 wire lines that run horizontal across all Trinitron screens. After about a year I didnt even notice them anymore.
About 2 weeks ago something new happened. I now have lots of lines running almost horizontal in straight lines across my screen, they tilt upward slightly. These are not like the two wire lines which are normal. They are only about an inch apart from one another so there are at least 15+ lines and they get a little closer together toward the top of the screen.
Depending on what application or game is running they are more visible at certain times. If I have black wallpaper you can see them very well. Also the lines seem to be green but they are very thin so its hard to tell.
Its not a video card problem because I checked that first. There are 1 or 2 pins missing from the head of the monitor cord but its been that way for over 3 years and this line thing is very new.
Any help with this problem is much appreciated, I spent hours googling this problem and all I could find were people complaining about the 2 wires that run across the Trinitrons which is normal and not this problem.
What refresh rate are you at? My G500 didn't handle high refresh rates to well after about 4-5yrs of service. Though it didn't get any lines like that.
Try lowering the refresh a notch and see if it does anything.
I had a similar situation happen to a couple of monitors at my workplace about 6 months ago. One had green lines, and the other had red lines. Also, the whole screen started to be tinted the same color. It that case, it was definitely not a video card problem. I found a bent pin in the monitor plug, but straightening the pin did not solve the problem either. I think your monitor is just dying.