How to Fix the Horizontal Lines on My Computer

By Dan Ketchum

Modern computer monitors, typically LCD displays, offer high-definition images and a sleek form factor. These energy-efficient screens contain liquid crystals between two sheets of polarized glass, sending electrical currents throughout the crystal molecules to create images. Couple this high-tech process with the fact that your monitor is also susceptible to software-based issues and it's little wonder that you may experience the occasional display error, including unattractive horizontal lines. When these appear, target software remedies before seeking professional assistance for hardware fixes.

Step 1

Check the HDMI, DVI, VGA or any other type of cable connecting your monitor to your computer, if you're using a desktop computer connected to an external monitor. Ensure the cable is securely connected to the respective input port -- in some cases, a loose connection can cause display errors.

Step 2

Download and install the most current hardware drivers for your Windows 8 operating system. Without the latest drivers, your LCD monitor may produce unwanted lines. Enter your computer's Settings menu, accessible by swiping from the right edge of the screen or hovering your mouse at the right edge, and choose “Change PC settings.”

Step 3

Click “Update and recovery” then select “Windows Update” and “Choose how updates get installed.” Under the “Important updates” section, select “Install updates automatically (recommended).” This ensures that your computer always has the most recent drivers, which may remedy your display issues. You may be prompted to restart your computer after installing the latest drivers.

Step 4

Update your video card drivers by accessing the Settings menu and choosing “Change PC Settings,” then “Update and recovery” and “Windows Update.” Select “Check now” and check under the “Optional” tab for updates pertaining to your video card -- click those updates to select them. Choose “Check for updates” and allow your PC to search for updates. Once the search finishes, click “Install updates” and then “Finish.” Without up-to-date drivers, your video card may cause display errors, choppy playback or error codes.

Tips & Warnings

  • Consult your monitor's manufacturer-provided user manual for model-specific troubleshooting procedures, but turn to professional technicians for hardware-based issues. For instance, cracked glass on an LCD screen or a loose internal video connection can cause one or many horizontal lines to appear -- this calls for professional repair from a service center authorized to work on your brand of monitor.
  • Debris such as dirt, dust, hair and crumbs can interfere with your monitor's internal connections if you're using a laptop, causing vertical or horizontal lines on the display. To prevent this, clean your device regularly with compressed air, targeting the air vents, ports and the spaces between the keys. For particularly dirty computers, give the laptop body a gentle-once over with a vacuum cleaner's soft-bristled attachment.
  • Older cathode ray tube monitors may display two faint horizontal lines when viewing lightly colored images. This is natural, as the monitors contain internal damper wires, horizontal connections that may cast a shadow on the screen.