I need some help. Yesterday, colored vertical stripes appeared across the screen. Then they merged into one black stripe, covering about 10% of the screen's width. The monitor is an LCD.
I suspected that the graphics card had failed, as I recently bought a used one. I replaced it with my old one, and the stripe disappeared. But today, it appeared again. It stayed for about 5 minutes and then disappeared again. And there's nothing I can really present to the service center. And I can't use the computer comfortably. What could be causing this?