What to Check When Testing a New Monitor
Quick answer: When testing a new monitor, check for dead and stuck pixels, backlight bleed and clouding, colour uniformity, and that it runs at its rated refresh rate — all before the return window closes. Each takes a minute in the browser.
Start here: open the dead pixel test and cycle through solid colours.
Dead and stuck pixels
Display solid red, green, blue, white and black and look for dots that are wrong. Our guides explain dead vs stuck pixels and how to check a monitor for dead pixels.
Backlight bleed and clouding
Show a full black screen in a dark room. Bright patches at the edges are backlight bleed and cloudy lighter areas are clouding — a small amount is normal, a lot is not.
Uniformity, colour and refresh rate
Display solid grey and white to spot tinted patches or uneven brightness, then confirm the panel runs at its advertised Hz — see a monitor stuck at 60Hz if it does not.
Do it within the return window
Run these checks as soon as the monitor arrives so you can return or exchange a faulty panel in time. Re-run the dead pixel test any time.
Why Test a New Monitor Right Away
The best time to test a monitor is the moment it arrives, while you're still inside the return window. Panels can have faults that aren't obvious until you look for them, and catching one early is the difference between an easy exchange and being stuck with it. A few minutes of checks tells you whether you got a good unit — and with panel quality varying even between identical models, that lottery is worth checking. Run through the tests below before you peel off all the protective film and commit.
The Essential Checks
- Dead and stuck pixels. Use the dead pixel test to cycle through solid colours and spot any pixels that don't match.
- Backlight bleed and glow. On a black screen in a dark room, look for bright patches around the edges or corners — some is normal, excessive bleed is not.
- Uniformity. On a solid grey or white screen, check for blotches, tinting or darker areas across the panel.
- Refresh rate. Confirm it runs at its rated rate with the refresh rate test.
- Resolution and scaling. Make sure it's set to its native resolution and that text looks crisp.
Motion, Colour and Sound
Beyond the basics, a few more checks catch the rest. Test motion clarity by dragging a window quickly or watching fast content — heavy ghosting or smearing trails behind moving objects suggests slow pixel response. Look at colour with varied images and photos; obvious tints or washed-out colour may need calibration or indicate a panel issue. Listen for coil whine or buzzing from the monitor, especially at certain brightness levels or refresh rates. And if it has speakers, give them a quick check. None of these takes long, and together they build a complete picture of the panel's health.
Buying a Used Monitor
For a second-hand monitor, the same tests matter even more, plus a few extras. Check the panel for burn-in or image retention (faint ghosts of static elements), more likely on OLED and older panels, by viewing solid colours. Inspect the physical condition — scratches, stand wobble, and that all the ports work. Power it through different inputs to confirm each one functions. Ask about hours of use if it's known. Running the full set of checks before money changes hands protects you from inheriting someone else's faulty panel, and gives you grounds to negotiate or walk away if something shows up.
Understanding Your Results
Once you've run the checks, the question is what's acceptable and what's worth returning. A single dead pixel at the edge is easy to live with and may fall within the maker's tolerance; one in the centre, or several, is a stronger case for exchange. Minor backlight bleed in the corners is normal on LCD panels and almost universal; large, uneven bright patches are not. Slightly off colour can often be improved with calibration rather than being a defect, while obvious tints or dead areas point to a faulty panel. The key is timing: most retailers give a return or exchange window of a couple of weeks, so test on day one, keep the packaging until you're satisfied, and photograph any fault on the test screen as evidence. That way, if something does turn up, you have both the time and the proof to act on it.
Frequently Asked Questions
What should I check on a new monitor?
Test for dead and stuck pixels, backlight bleed, panel uniformity, the rated refresh rate, native resolution and text sharpness, motion clarity (ghosting), colour, and any coil whine. Do it within the return window so a faulty unit can be exchanged.
How do I check for backlight bleed?
Display a full black screen in a dark room and look for bright patches or glow around the edges and corners. A little is normal on LCD panels; large, uneven bright areas are excessive bleed worth returning the monitor over.
What is monitor ghosting?
Ghosting is a faint trail behind fast-moving objects, caused by slow pixel response. Test it by dragging a window quickly or watching fast motion. Heavy ghosting points to a slow panel; some gaming monitors offer an overdrive setting to reduce it.
What extra checks matter for a used monitor?
On top of the usual tests, look for burn-in or image retention by viewing solid colours, inspect for scratches and stand wobble, and confirm every input port works. Doing this before you pay protects you from a faulty panel.
How long do I have to return a faulty monitor?
It varies by retailer, but return or exchange windows are commonly around two weeks to a month. Test the monitor the day it arrives, keep the packaging until you're happy, so a fault can be returned well within the window.
Is some backlight bleed normal?
Yes. Minor bleed or glow in the corners is normal and almost universal on LCD panels. It's only a problem when it's heavy and uneven — large bright patches across the screen on a black image are worth returning the monitor over.
What is panel uniformity?
Uniformity is how evenly brightness and colour are spread across the screen. On a solid grey or white image, blotches, darker zones or colour tint bands indicate poor uniformity, which is hard to fix and worth checking within the return window.
Should I calibrate a new monitor?
Calibration improves colour accuracy and is worth it for photo and video work. Many monitors are accurate enough out of the box for general use, so calibrate if colour matters to you, but it isn't essential for everyday tasks.
What is image retention?
Image retention is a temporary faint ghost of a static image that lingers briefly after it changes, then fades. It differs from permanent burn-in. Some retention is normal on certain panels; persistent, permanent ghosting is the fault to watch for.
Does a new monitor need a break-in period?
No, there's no real break-in needed. Test it fully on arrival rather than waiting. Pixels and panels don't improve with use, so any faults present from new should be caught within the return window.
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