Get a new computer, it sounds like this one is pretty well fudged up!!!!
If putting a known good monitor on your PC gives you a green screen, then something is broken. Probably your video card.
did you put a magnet on it? usually that is the cause no
3 - Red, blue and green.
Red, Blue, and Green
Red Green Blue
Your video cars ram is probaly failing...
Red, Green & Blue.... Hence the term 'RGB monitor'.
Red,Green, and Blue. Have you ever wondered why they call the input RGB?
This happened to me too. I replaced my monitor cable and that fixed the problem. I think it has something to do with the fact that VGA carries three colors: red, green and blue. One of the connections within the cable must have gone bad.
A screen/monitor that only shows one color except for black. Like a black and white TV or a green and black cell-phone screen.
The green screen doesn't look green on T.V. because on the set for whatever they are doing the camera people put a backround on the green screen. That way you don't see the green screen only the backround. The people on set see the green screen.
A green light on your computer monitor i think means that it is on. im not sure though