New Monitor Checklist: 7 Things to Test for Defects the Day It Arrives
When a new monitor arrives, it pays to check the screen properly once before you start using it. Retailers usually accept returns or exchanges for defects only for a short time, and if you notice a problem later you may not be able to get one. This guide covers what to check on day one, including dead pixels, backlight bleed, uneven color, banding and crushed blacks, and how to look for each using full-screen solid colors and gradients.
Why you should check for defects the day it arrives
Most retailers exchange or refund defective products only for a short time after purchase. The window varies from a few days to about a month depending on the store; after that it usually becomes a manufacturer warranty repair, and it can take a while to get the monitor back.
- Keep the box, packing material and accessories until you've finished checking
- Have the receipt or order history showing the purchase date to hand
- Find out the store's return window for defects and how to apply
The check itself takes about 15 minutes: you only need to show solid colors and gradients full-screen in a browser. Once the monitor is set up and switched on, get it done before you start on any other settings.
7 things to check when it arrives
| Item | Screen to use | Signs of a defect |
|---|---|---|
| Dead pixels | Solid black, white, red, green, blue | Dots that stay lit or never light |
| Backlight bleed | Black, in a dark room | Whitish light seeping from edges or corners |
| Uneven color | White and gray | Areas that look yellowish, bluish or darker |
| Banding | Gradient | Stripes in what should be a smooth color change |
| Crushed blacks / blown-out whites | Black and white level steps | You can't tell the darkest or brightest steps apart |
| Refresh rate | Measurement screen | The advertised value isn't reached |
| Ports and display | Normal use | Flicker, signal dropping out, buttons not working |
Working from the top down groups the dark-room checks and the normal-light checks together, so it goes quickly. The Screen Checker's Dead pixels & burn-in screen steps through solid black, white, red, green and blue, gray, a gradient, black and white level steps, and a 1px checkerboard.
Checks in a dark room: dead pixels and backlight bleed
First darken the room, turn the monitor's brightness to maximum and show a full-screen black image. This is when stuck bright pixels and backlight bleed are easiest to spot. For a detailed look at dead pixels, see how to check for dead pixels.
An LCD monitor makes black by using the liquid crystal layer to block light from the backlight behind it. Depending on how the panel is assembled, light can seep out from the edges or corners. This is called backlight bleed.
Most monitors show some bleed in a dark room at maximum brightness. A realistic test is to return to your normal brightness and see whether it still bothers you in dark film or game scenes.
Checks at normal brightness: uniformity, banding and levels
Next, return the room to its usual lighting and set the monitor's brightness to what you'll actually use.
- 1
Check uniformity with white and gray
See whether the whole screen looks like the same color. Compare the center with the four corners for areas that look yellowish, bluish or darker. A darker gray shows unevenness more easily than white.
- 2
Check banding with a gradient
On a screen that fades smoothly from black to white, look for distinct stripes. Faint steps come from the number of colors the panel can show and are usually not a defect.
- 3
Check for crushed blacks and blown-out whites with level steps
Show 16 bands that differ slightly in brightness and check that you can tell apart the steps at both the dark and bright ends. If many can't be distinguished, review the monitor's brightness, contrast and gamma settings.
- 4
Check sharpness with a 1px checkerboard
Make sure the fine checkerboard looks crisp. If it blurs into a gray surface, the PC's resolution may not match the monitor's native resolution.
What to prepare if you find a defect
If something bothers you, gather the details before contacting the store. A photo communicates the problem more accurately than a description.
- Photos showing the problem: shoot dead pixels up close on a solid-color screen, and bleed from straight on in a dark room. Phone cameras tend to brighten scenes, so lowering the exposure a little makes the photo closer to what you see.
- Model name, serial number and purchase date
- Which screen, where on the screen and what symptom
- PC settings (resolution and refresh rate) and the type of cable
If the refresh rate isn't reaching the spec, the cause is often the settings or cable rather than the monitor, so work through how to check your refresh rate first. If traces of text remain after long use, telling image retention from burn-in will help.
FAQ
- What should I check when a new monitor arrives?
- Seven things: dead pixels, backlight bleed, uneven color, banding, crushed blacks and blown-out whites, refresh rate, and whether the ports and picture are stable. Showing solid colors and gradients full-screen lets you get through them all in about 15 minutes.
- What's the difference between IPS glow and backlight bleed?
- IPS glow is a property of IPS panels and changes a lot as you change your viewing angle. Backlight bleed stays in the same place whatever the angle. Moving your head from side to side tells them apart.
- How long is the return window for a defective monitor?
- It depends on the retailer, commonly from a few days to about a month. Check your store's policy and finish your checks within that time. After it ends, the monitor is usually handled as a manufacturer warranty repair.
- Is it a defect if I see stripes in a gradient?
- Faint steps come from the number of colors the panel can show and are usually not a defect. If you see thick, distinct stripes or bands of unnatural color, check your settings and then contact the store.
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