[paul9]

Thin, angled lines are generally frame flyback lines. Those happen when the electron beam doesn't blank properly when it returns from the bottom of the screen back to the top to start drawing the next frame. Horizontal bands drifting up or down the screen can be caused by outside interference amonst other things and may be cured or lessened by using a better shielded monitor cable, a shorter cable, or rerouting the cable. Sometimes.