Dead and stuck are different faults
A dead pixel is permanently off and shows black on every colour. It is a failed transistor and cannot be repaired.
A stuck pixel is permanently on in one colour — a bright red, green or blue dot visible on a black screen. Those sometimes recover, either on their own or with software that cycles colours rapidly at that spot for an hour or two.
Which is why cycling through solid colours finds both: black reveals stuck pixels, white reveals dead ones, and the primaries reveal a subpixel failure that neither shows.
Do it while you can still return it
Manufacturers have a pixel policy, and most permit several dead pixels before a panel counts as faulty — the threshold is often three or more, and stricter for professional monitors. A retailer’s return window is usually the better route, and it closes.
Test a second-hand screen before money changes hands. It takes thirty seconds and is the single most useful check you can make.
Frequently asked questions
What is the difference between a dead and a stuck pixel?
A dead pixel is always black; a stuck one is always lit in a colour. Stuck pixels sometimes recover, dead ones do not.
Can a stuck pixel be fixed?
Sometimes, by cycling colours rapidly at that point for an hour or two. It works often enough to be worth trying and is not guaranteed.
How many dead pixels before a warranty claim?
It depends on the manufacturer — often three or more, and stricter for professional monitors. The retailer’s return window is usually easier.
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