Occasionally when I leave the computer for a couple of hours, on my return the monitor is covered with horizonal lines about an eighth of an inch apart. I have an LCD monitor, and a desktop computer which was virtually rebuilt last Spring. Any ideas what's causing this please?
Turn the monitor off immediately after boot-up, leave it off for a couple of hours then turn it on again. If the lines aren't there, then it looks like a monitor problem. If the lines are there, then I think it's a graphics card heat problem.