I don't know if this is the right forum for this; please move it if it belongs elsewhere. I have a very strange problem with my monitor. After the computer has been left for a while (and I think sometimes if it is put on standby) and then we come back to the computer to use it, the screen starts to do something very weird. First, the desktop appears and dissappears repeatedly, but when it appears, it doesn't just flash on the screen, it starts out as a vertical line in the middle of the screen, then stretches horizontally til it fills the screen, then flashes off (then it starts back as the vertical line). It does this 7-8 times, then either it collapses to a vertical line, and then the display goes out altogether (black screen), or the screen starts to shake. If it starts to shake, the shakes gradually slow down and it goes back to normal. The shaking is sort of like how the computer looks when you degauss it, but it's not exactly the same. It's an old monitor that my mom's work was giving away and we took it. The computer itself is fine I think. Why would something like this happen? Thanks.