Cracked, black or flickering: what is actually wrong with your screen

The external monitor test

This is the single most useful check, and it settles more cases than everything else combined. Connect the laptop to an external monitor or television. If the external display is perfect, the problem is in the screen, its backlight or its cable — the computer itself is fine. If the same distortion, artefacts or coloured patterns appear on the external display too, the fault is on the graphics side, and replacing the screen would not fix it. That distinction is often the difference between a modest repair and a major one, so it is worth doing before agreeing to anything.

Reading the symptom

Each pattern points somewhere fairly specific.

• Cracked with spidering or ink-like blotches — the panel itself is physically damaged and needs replacing
• Very dark but a faint image visible under bright light — classic backlight failure — the panel is working, the illumination is not
• Flickering that changes when you move the lid — usually the display cable or a hinge straining it, not the panel
• Distortion that also appears on an external monitor — graphics hardware, not the screen
• A few permanently coloured dots — dead or stuck pixels — cosmetic, and rarely worth replacing a panel over
• Nothing at all, no fans, no sound — not a screen problem — this is power or startup

Why a loose hinge is urgent

A hinge that has gone stiff or loose is easy to ignore, and it is the fault most likely to escalate. The display cable runs through the hinge area, so every open and close of a damaged hinge stresses that cable and the lid around it. What starts as an annoyance becomes a flickering display, and eventually a cracked panel or a torn cable. Fixing a hinge early keeps the repair small — leaving it reliably makes it larger.

What not to do

Do not press on a cracked panel to see how bad it is; you will spread the damage. Do not keep opening and closing a lid that flickers, for the reason above. And do not leave a cracked screen indefinitely on the basis that it still works — cracks admit dust and moisture, spread under normal use, and can eventually take the digitiser or cable with them.