Dead Pixel Test · Guide
White Screen Test
A pure white field drives every subpixel fully on, so anything that stays dark stands out. Run it from the main test page — press Start Test there — and judge with your own eyes. This is a visual check only.
What white reveals
On pure white, a dead pixel receiving no power stays black on every background and is easiest to confirm here. Dust and smudges also show up clearly, which is why most first reports turn out to be dust, not pixels.
Use your normal brightness. Extreme brightness can dazzle and hide a faint dark dot; a dark room makes white uncomfortably harsh.
How to run it
Press Start Test on the main page and step to the white field. Scan the full area, then press H to hide the controls and re-check the edges and corners where faults are easiest to miss.
Confirm every suspect on black as well: black on every colour means a suspected dead pixel, while a dot that glows one fixed colour on dark fields but vanishes on white means a suspected stuck pixel.
Dust versus a real fault
Tilt the screen: dust sits on the glass above the panel, looks blurry and shifts relative to the image, and often wipes away with a soft, dry microfibre cloth. A faulty pixel stays sharp, fixed and exactly one dot wide.
Mark a surviving suspect on the screen map and download the text summary as your “User-reported visual inspection” note — your record, not a diagnosis or warranty certificate.
Honest limits: this guide helps you identify possible display problems with your own eyes. It cannot repair hardware pixels, diagnose your display automatically, or decide warranty claims. Read the limits.
Guide FAQ
What does a white screen test show?
Dark dots on a fully lit field: suspected dead pixels, plus dust that should be ruled out first by tilting the screen and wiping gently.
Is one dark dot enough for a warranty claim?
Not necessarily. Whether faulty pixels qualify for repair depends on the manufacturer’s pixel policy, which often tolerates a few defective pixels per panel.