Thin coloured lines run across the screen, sometimes flickering, sometimes fixed in place. When Windows 10 horizontal lines on screen appear, the worry is that the dewaasia display is dying.
Lines can come from three places: the graphics driver, the cable or connection between the computer and the screen, or the screen panel itself. Only the last one requires a repair.
A simple test separates them. Lines produced by software disappear when Windows is not running, while lines produced by hardware remain visible everywhere.
That test should be your first step before spending money.
The lines may be one pixel thin or several centimetres wide, steady or flickering, and they may change colour. Each pattern gives clues about where the fault lies.
Possible Causes
Horizontal lines appear for these reasons:
- An outdated or faulty graphics driver.
- A loose, damaged, or low-quality display cable on external monitors.
- A refresh rate or resolution the monitor does not handle well.
- A damaged laptop screen, display cable inside the hinge, or failing graphics chip.
Lines that change when you move the laptop lid point strongly to the internal display cable.
Quick Fixes to Try First
Run the BIOS test.
- Restart the PC and enter the BIOS or UEFI setup using the key shown at startup.
- Look at the screen there. If the lines are still visible, the fault is hardware.
- If the BIOS screen is clean, return to Windows and continue with software checks.
- For external monitors, reseat or replace the cable.
- Set the resolution and refresh rate to the recommended values in Display settings.
For laptops, gently open and close the lid while watching the lines to check whether the hinge cable is involved.
Advanced Steps for Stubborn Cases
Fix software or confirm hardware.
- Download the latest graphics driver from the manufacturer and perform a clean installation.
- If lines began after a driver update, roll back the driver in Device Manager.
- Connect the laptop to an external monitor. Clean output there means the laptop screen or its cable is faulty.
- Take a screenshot. If the lines do not appear in the screenshot, the problem is in the display hardware, not Windows.
- If the hardware is at fault, arrange a repair through the manufacturer or a trusted repair shop.
Before You Go Further: Keep Your Files Safe
Back up important files if the graphics chip may be failing, since that can lead to crashes. Avoid pressing on the screen to “fix” lines, which can cause more damage.
Conclusion
Horizontal lines can come from drivers, cables, or the screen itself. The BIOS and screenshot tests show whether software or hardware is responsible.
Taking a phone photo of the lines before visiting a repair shop helps the technician, especially if the lines come and go.
