LaptopCheck
Stage 2 of 7 · 🔴 Critical

Display & screen test

The screen is the single most expensive part to replace, and dead pixels or backlight bleed are easy to hide during a quick glance. Five minutes of fullscreen colour tests settles it.

⏱️ Whole stage ≈ 9 min (first time)

🛠️ Technical checks

  • Open pixel-test site & cycle colours ~4 min

👁️ General checks

  • Backlight bleed / pressure marks ~2 min
  • Brightness & flicker ~2 min
  • Touchscreen / viewing angles ~1.5 min
🌐

Best tool for this stage: a free fullscreen pixel test website — no install needed. Open one of these and press F11 for true fullscreen: deadpixeltest.org, deadpixel.tools, or EIZO Monitor Test (more thorough).

1

Clean the screen first Important

So dust isn't mistaken for a dead pixel
  • Wipe the screen with a dry microfibre cloth — smudges and dust look just like stuck pixels.
  • Set brightness to maximum for the pixel tests.
  • If possible, dim the room slightly so subtle defects stand out.
2

Hunt for dead & stuck pixels Critical

Cycle solid colours fullscreen

Open a pixel-test site, go fullscreen, and step through each solid colour. Put your face close and scan the whole panel, including the corners.

  • Black screen: look for any pixel glowing white/coloured — that's a stuck pixel.
  • White screen: look for black dots — that's a dead pixel. Also spot any dust/spots behind the glass.
  • Red, Green, Blue screens: any pixel that stays the wrong colour stands out clearly.
⌨️

No internet at the seller's? Open Windows Paint, hit Ctrl+E, set canvas large, fill with the bucket tool, and maximize — or open a plain colour image saved on your USB stick.

✓No dead/stuck pixels, or one tiny stuck pixel you can live with.
✕Clusters of dead pixels, a dead pixel dead-centre, or a visible line of pixels — use it to negotiate hard or pass.
3

Check backlight bleed & IPS glow Important

Most visible on a pure black screen

With the black screen still up and the room dim:

  • Backlight bleed: bright patches or "clouds" leaking from the edges/corners. A little is normal; large bright zones are not.
  • IPS glow: a faint glow in the corners that shifts as you change viewing angle — normal on IPS panels, not a defect.
  • Also check for pressure marks (dark blotches) or scratches on the white screen.
4

Brightness, uniformity & flicker Important

Confirms the backlight and panel are healthy
  • Brightness range: press the brightness keys (usually Fn + F-keys) from min to max. It should change smoothly and get genuinely bright.
  • Uniformity: on a grey or white screen, look for areas that are noticeably darker/yellower than the rest.
  • Flicker: watch a white screen for any flickering or buzzing, especially at lower brightness (PWM flicker or a failing backlight).
  • Banding: a smooth gradient should look smooth, not stepped.
⚠️

A screen that flickers, won't go bright, or has a permanent tint can mean a failing backlight or loose display cable — both annoying and costly.

If it's an OLED screen — check for burn-in

OLED panels (common on premium ultrabooks) can suffer burn-in: faint permanent ghosts of the taskbar, app icons or a logo. On a solid grey and then white screen, look for any static shapes that don't belong. Light, even ageing is normal on older OLEDs, but a clear ghost of the taskbar is a defect worth pricing in.

5

Touchscreen & viewing angles If applicable

Only for touch / 2-in-1 models
  • If it's a touchscreen: open Paint or the on-screen keyboard and drag across the entire surface — every area should respond with no dead zones.
  • Viewing angles: tilt the screen. Colours should stay stable on an IPS panel; heavy colour shift suggests a cheaper TN panel (fine, just know what you're getting).
  • Glossy vs matte: confirm the finish matches the original — a mismatched replacement screen is a clue to past repair.