DeviceOK
SearchDevice checks
Home / Checks / Used Monitor Check
Used monitor and display buyers

Used Monitor Check

Inspect a used monitor for fixed pixel defects, dark-screen uniformity, gradients, sharpness, native resolution and refresh behavior before paying or accepting the display.

Inspection principle

Panel defects are easiest to find with controlled full-screen patterns, but a purchase decision also depends on inputs, stand/mount condition, power stability and whether the monitor actually reaches its advertised modes on a compatible source.

Progress0 of 11 checks recorded
Run next live test ↗

Run the browser-visible checks, then record the physical/native checks below. Progress stays in this browser unless you deliberately copy the fragment share link.

Live evidence

Browser-visible checks

1
Dead / stuck pixelsShow solid colors full-screen so you can visually inspect for dead or stuck pixels.
Run test ↗
2
Dark-screen uniformityShow a black full-screen pattern for visual backlight bleed inspection.
Run test ↗
3
Gradient qualityDisplay smooth gradients to inspect visible color banding.
Run test ↗
4
Text / edge sharpnessDisplay fine lines and text patterns to inspect scaling and sharpness.
Run test ↗
5
Active resolutionShow browser viewport, screen dimensions, and device pixel ratio.
Run test ↗
6
Refresh timingEstimate display refresh timing using animation frames.
Run test ↗
Outside the browser

Physical & native checks

These close the blind spots a website cannot inspect.

1
Panel surface and bezel

View the screen off and on under side lighting for scratches, pressure marks, coating damage, cracks and bezel separation.

Why it matters: Surface damage can be invisible on a bright desktop but obvious in dark content.
2
Each input you plan to use

Test the required HDMI/DisplayPort/USB-C input with a known-good source and cable; do not assume one working input proves the others.

Why it matters: Inputs often use different signal paths and can fail independently.
3
Advertised resolution/refresh mode

Confirm the OS actually offers the target resolution and refresh rate using a source/cable capable of that mode.

Why it matters: A 60 Hz fallback can be a cable/source limit rather than a panel fault.
4
Stand, VESA threads and adjustments

Check wobble, tilt/height/pivot mechanisms and VESA threads if you will mount it.

Why it matters: Mechanical damage affects usability and replacement cost even when the panel works.
5
Cold start and sleep/wake

Power-cycle once and test sleep/wake or input reacquisition.

Why it matters: Power-board or handshake problems may appear only during state changes.
Stop / escalate

Conditions that deserve caution

  • Cracked panel, expanding dark areas or obvious pressure damage.
  • Intermittent power or signal loss repeats across known-good cables/sources.
  • Required native resolution/refresh cannot be reached after source/cable capability is verified.
Decision rule

How to use the evidence

Separate panel faults from signal-path faults: repeat a visual defect on more than one input/source before blaming the panel; repeat signal loss with a second known-good cable before blaming the monitor.

0 passed0 need attention0 skipped