When working on a computer, you need a clear and stable picture. Sometimes the vertical line goes haywire and your screen messes up, making things hard to watch. Acer monitors come with controls that will adjust the horizontal line settings. There's no need to take your Acer monitor to the repair shop, nor do you need to buy another monitor. Try fixing the problem on your own and save some money.
Press the first menu button; it will be the button closest to the right-hand side. This will bring a menu on the screen to show you which button to press for the OSD. You will find five buttons at the bottom of the Acer monitor. Look for the image that indicates OSD. This image can look like a rectangle with lines across it, or it may say "OSD."
Press the corresponding button for the OSD. The OSD is usually the third option.
Press the up and down arrow keys to select the "H. Position" option.
Press the up and down keys to adjust the sliding scales.
Press the menu key again to keep the settings you want.