Lines, white patches and a dim picture on a laptop screen each point to a different part. Connect an external monitor first: if the monitor looks clean, the fault is in the laptop's own panel, its display cable or its backlight, and a screen repair will usually fix it. If the monitor shows the same problem, the cause is the graphics side or the motherboard, and replacing the panel would waste money. This one test settles most cases in a couple of minutes.
The guide below explains what each symptom usually means, which checks you can do safely at home, when a software fix is worth trying and when the screen needs replacing. It will not diagnose your exact laptop, because the same picture can come from more than one cause, but it will tell you what to ask for at the inspection.
The test that separates screen faults from graphics faults
You need a monitor or TV and an HDMI cable, or a USB-C cable if your laptop has a video-capable USB-C port. Connect it, press the Windows key and P together, and choose "Duplicate" or "Second screen only". Then look at the external picture.
- External display is clean: the laptop is producing a good picture. The fault lies in the laptop's own panel, the cable that carries the picture to it, or the backlight.
- External display shows the same lines or glitches: the picture is already damaged before it reaches any screen. That points to the graphics driver, the graphics chip or the board.
- External display shows nothing: note it and tell the technician, because it suggests a fault in the video output itself, unless the cable, the input or a USB-C port without video is to blame.
Two quick extras. Press the Windows key, Ctrl, Shift and B together: the screen blinks as Windows restarts the graphics driver, and a driver glitch may clear. And look at the first start-up screen, or open the BIOS. If the fault is already there before Windows loads, software is not the cause.
What each symptom usually means
| What you see | Likely causes | What to try first |
|---|---|---|
| Vertical coloured or white lines | Panel damage, a loose or worn display cable, or a graphics fault if the monitor shows them too | External monitor test, then open the lid slowly to see whether the lines change |
| Horizontal lines or a band across the picture | Display cable, panel or the graphics side | The same test, and a driver restart |
| Flicker that changes as you move the lid | The display cable or its connector, strained by the hinge | Stop moving the lid and have it inspected, because it will tend to get worse |
| Dim picture, but you can see a faint image with a torch | Backlight failure, either in the panel strip or the circuit that feeds it | Check brightness keys and power-saving settings, then external monitor test |
| Solid white screen | Cable, panel or board | External monitor test, and watch for the boot logo |
| Pale or bright patches, or uneven brightness | Pressure on the panel or damage to its backlight layers | Do not press on the lid or the screen; a new panel is usually the fix |
| Ink-like blotches or colour patches spreading from one spot | Pressure or impact damage to the panel | Stop using it and avoid pressing on the lid; a new panel is the fix |
| Pink, green or washed-out colour | A driver or colour profile setting, or a failing cable | Roll the graphics driver back, reset the colour profile, then test again |
| A few bright or dark dots | Stuck or dead pixels | Show a full-colour test screen; stuck pixels sometimes clear, dead pixels cannot be repaired. Do not press on the panel |
The torch test for a dim screen
When the picture seems to be missing but the laptop is clearly on, shine a torch at the screen from an angle in a dim room. If you can make out faint icons, the panel is working and its backlight is not. That is a different repair from a dead panel, and it is worth telling the technician because the answer may be the backlight circuit or the light strip, not the whole display.
What not to do
- Do not press on the screen to "settle" the lines. Pressure is a common way to turn a cable fault into a panel fault.
- Do not keep using a screen whose damage is spreading. It will not heal, and the cost of repair can rise.
- Do not spray cleaner on the screen. Liquid runs under the bezel, and the screen needs a dry or lightly damp soft cloth.
- Do not prise the bezel open. It is held by adhesive or fragile clips, and the cable underneath tears easily.
When the screen needs replacing
A panel with physical damage, ink patches, or a backlight that has failed is replaced, and so is a panel whose lines stay in the BIOS and on the boot logo once the cable has been ruled out. The replacement must match the original: the same size, the same resolution, the same refresh rate, touch or no touch and the same connector. Screens that look identical can have different connectors, so the model number matters more than the picture. Our page on laptop screen types explains how the panels differ.
When a cable is at fault, replacing the cable is cheaper than replacing the panel, and a good inspection tells the two apart. The usual order is to test the cable and connector, then the panel, because a new panel on a bad cable would show the same fault. If the external monitor showed the problem too, the next step is the board, not the screen. You can read how screen jobs are priced in our laptop screen replacement cost guide, and whether to repair or replace a cracked panel in repair or replace a cracked screen.
How the work goes at Xigox
Ring or message us, and we collect the laptop within 2 hours of the booking. The ₹350 inspection finds out which of the causes above you have, and it is credited to the bill if you proceed. The written quote then states whether it is a cable, a panel or something else, and names the panel type. Many screen jobs are completed the same day when the right panel is available, and a rare model may need to be ordered, which we tell you at the quote. The repair carries a 90-day warranty.
See the pages for screen replacement and screen repair to see what is covered, or start with laptop screen replacement near me and laptop repair near me to see where to book. Our flickering screen guide and the one on a black screen on a running laptop cover two neighbouring problems.
Frequently asked questions
Can lines on a laptop screen go away on their own?
Lines caused by a driver glitch can clear after a restart or a driver update. Lines caused by the panel or the cable usually stay and often spread, so they are worth checking early.
Is it the screen or the motherboard?
The external monitor test answers it. A clean external picture points to the screen side. The same fault on the monitor points to the graphics side or the board.
Is it safe to keep using a laptop with lines on the screen?
The laptop itself is not at risk, but the picture can get worse and your files are harder to work with. Back up your files and have it looked at sooner rather than later.
How long does a screen replacement take?
Often the same day when the panel for your model is on hand. A less common panel may need to be ordered, and the quote tells you the expected date.
