A Chromebook screen that flickers, flashes black, or fills with colored lines can make even simple tasks impossible. The frustrating part is that a ChromeOS glitch and a failing display cable can look almost identical.
I would not start with a factory reset. Two quick checks, using an external screen and comparing a screenshot with what you can actually see, can tell you much more about where the problem is coming from.
The steps below work as a diagnostic guide for Acer, ASUS, HP, Lenovo, Dell, Samsung, and other Chromebooks, although hardware-reset methods and display connections can vary by model.
First, identify what your Chromebook screen is doing
Look for the pattern before changing settings. A screen that glitches only in YouTube needs a different approach from one that shows vertical lines before you even sign in.
| What you see | What to check first |
|---|---|
| Flickering only in Chrome, YouTube, or one app | Test another app, Guest mode, and extensions |
| Colored or vertical lines that stay in one place | External monitor and physical screen damage |
| Picture changes when you move the lid | Possible display cable or hinge-area connection |
| Whole screen flashes after waking from sleep | Full restart, ChromeOS update, then hardware reset |
| Screen goes black but Chromebook stays powered on | Brightness, external monitor, power, and display connection |
| Glitches appear on both built-in and external displays | ChromeOS, graphics processing, or a wider system fault |
These are clues, not guaranteed diagnoses. For example, a graphics problem can sometimes affect one display path more than another.
Test the screen before resetting anything
1. Connect a TV or external monitor
Connect your Chromebook to a working monitor or TV using a supported HDMI or USB-C display connection. Use a compatible adapter if your model requires one.
- Turn on the external screen and select the correct input.
- On the Chromebook, select the time, open Settings, and search for Displays. On many versions, it appears under Device > Displays.
- Choose Mirror Built-in Display if you want both screens to show the same content.
- Watch both displays while the glitch happens.
External screen looks normal, built-in screen glitches: The internal panel, its cable, or the built-in display connection becomes a stronger suspect. Continue with the screenshot and lid tests before paying for repair.
Both screens glitch at the same time: A ChromeOS, app, or graphics-processing problem becomes more plausible, although it is not proof of a software fault.
If only the external monitor flickers, test another cable, port, adapter, or supported refresh rate. That is a different issue from a damaged Chromebook display. Google explains the connection and display controls in its Chromebook external-monitor guide.
2. Compare a screenshot with a phone photo
When the glitch is visible, capture a screenshot with Ctrl + Show windows. You can also use the Chromebook’s Screenshot key, if it has one, or select Screen capture from Quick Settings.
Then take a photo of the physical screen using your phone. View the screenshot on a different device or an external monitor, not just on the faulty Chromebook screen.
- Screenshot is clean, phone photo shows lines: The issue may be occurring after the image is rendered, such as in the built-in panel or display path.
- Screenshot contains the same distortion: The glitch may originate in the rendered content, app, or graphics pipeline.
This test is useful but not conclusive. Some graphics failures do not appear in screenshots, and brief flickers may disappear before the capture. If a screenshot is clean but the internal screen still glitches, combine that result with the external-monitor test rather than treating it as proof of a broken panel.
3. See whether the glitch follows the lid
With the Chromebook on a stable surface, gently move the lid through its normal range. Do not bend, twist, or force the hinge.
If the picture cuts out or colored lines change at a particular angle, an internal display cable or hinge-area connection may be loose or damaged. This is especially concerning if the Chromebook was dropped or the hinge feels stiff.
Stop repeatedly moving the lid once you notice a consistent connection. Back up important files while the screen is still usable and arrange a manufacturer or repair-shop inspection. A Powerwash will not reconnect a damaged cable.
Fix flickering that appears to be caused by ChromeOS
If the external monitor test does not point clearly to the built-in screen, or the glitch began after sleep or an update, work through these software checks in order.
Fully shut down and restart
Closing the lid normally puts a Chromebook to sleep. For this test, select the time, choose Power, wait until the Chromebook turns off, then turn it back on.
Disconnect external monitors, USB-C docks, and accessories before restarting. Test the screen before opening a long list of apps.
A glitch that disappears after a full shutdown may have been caused by a temporary display or graphics state. If it keeps returning after sleep, note that pattern for the later hardware-reset step.
Check whether only one app or website is affected
Open ChromeOS Settings, the Files app, and a normal webpage. Then test the app or video that originally triggered the problem.
When Settings and the desktop are stable but one website flickers, close that tab and reopen it. Test the same content in a different tab or app. If the problem occurs only with one streaming video, try another video and check whether the app has an update available.
Browser extensions can also interfere with page rendering. To test them, open Chrome > Extensions > Manage extensions, temporarily turn off recently installed extensions, and retest the affected page. Restore extensions one at a time to identify a conflict.
Do not change experimental chrome://flags settings at random. Those options can change between ChromeOS versions and may create new display problems.
Test in Guest mode
Guest mode is helpful when the flicker seems tied to your normal Chrome profile.
- Sign out of your Chromebook.
- On the sign-in screen, choose Browse as Guest.
- Open a few ordinary webpages and check whether the glitch returns.
Stable in Guest mode: Look more closely at your account’s extensions, settings, or apps. Still glitching in Guest mode: The problem is less likely to be limited to one Chrome profile.
Guest browsing may be disabled on school or work Chromebooks. If the option is missing on a managed device, contact the administrator rather than attempting to bypass management.
Install an available ChromeOS update
Open Settings > About ChromeOS > Check for updates. Install any available update and restart when prompted.
ChromeOS updates can address software and device-compatibility problems, but an update is not guaranteed to repair a faulty display panel. If the flicker began immediately after an update, record the ChromeOS version and the Chromebook model so you can report the issue accurately.
Google’s Chromebook update instructions confirm the current update path.
Check display settings if the screen looks wrong rather than physically broken
Not every unusual screen is actually flickering. Unexpected zoom, rotated content, inverted colors, or a warm tint can be mistaken for a display malfunction.
Open Settings and search for Displays. Select the built-in display and review its display and text size and orientation. Return accidental changes to your preferred values.
For odd colors, check Night Light under Displays. Also review Settings > Accessibility for color inversion, color correction, or magnification settings that may have been enabled unintentionally.
These settings will not repair a screen with physical cracks or persistent vertical lines. They are worth checking only when the image is stable but its appearance has changed.
Try a Chromebook hardware reset when the flicker returns after sleep
Google calls this a hard reset. It restarts Chromebook hardware components and is different from the Powerwash factory reset.
For most Chromebooks with a built-in keyboard:
- Turn the Chromebook off completely.
- Press and hold the Refresh key.
- While holding Refresh, tap the Power button.
- Release Refresh when the Chromebook starts.
Some Chromebook models and tablets use different button combinations. Follow the instructions for your exact model if the standard shortcut does not apply.
Important: Google warns that a hardware reset might delete some files from the Downloads folder. Back up important local files before attempting it when possible. See the official hardware-reset instructions.
If your keyboard or touchpad is malfunctioning alongside the screen, see my guides on Chromebook keyboard not working and Chromebook touchpad not working. Problems affecting several built-in components at once deserve closer hardware investigation.
What to do about horizontal lines, vertical lines, and black patches
Lines that stay in the same position, colored blocks, a spreading black patch, or a visible crack are stronger indicators of a physical screen problem than an occasional app flicker.
Check whether the distortion appears on the startup screen or sign-in screen before opening your apps. If it does, your Chrome profile and extensions are unlikely to explain it. Compare the result with an external display.
A clear external picture combined with persistent internal lines often points toward the LCD panel, internal display cable, or display connector. The exact component still requires inspection.
A Chromebook that was dropped, exposed to liquid, or has a damaged hinge should be assessed for physical damage. Do not press on the screen to make lines disappear, and do not open the display bezel unless you have the correct repair procedure and equipment.
If the display is unreadable but the external monitor works, use the external screen to back up important local files before arranging repair.
Should you Powerwash a Chromebook with a glitching screen?
Only consider a Powerwash when the evidence points to a persistent ChromeOS or account problem and the less destructive tests have failed. It is usually a poor choice when the internal screen changes with lid movement, has impact damage, or shows the same fixed lines before sign-in while an external monitor is clear.
Powerwash erases locally stored user data, including files that have not been backed up from Downloads. Save important files to Google Drive or external storage first and make sure you know your Google Account credentials.
If you decide a factory reset is appropriate, sign out and press Ctrl + Alt + Shift + R, select Restart, then follow the Powerwash prompts. Managed school or work devices may require administrator assistance.
Google’s factory-reset guide explains what is erased and recommends trying extensions and a hardware reset before Powerwash.
When a screen repair is the better next step
I would contact the Chromebook manufacturer or a reputable repair provider when several of these signs appear together:
- The built-in screen glitches but a connected external display remains clear.
- Lines change or the image cuts out when the lid moves.
- Distortion is visible before you sign in.
- The screen has a crack, dark patch, liquid damage, or signs of impact.
- Restarting, updating ChromeOS, and the appropriate hardware reset make no difference.
Give the repair provider your Chromebook’s exact model, when the glitch began, and the results of the external-monitor test. A short phone video of the fault can be more useful than describing it as “the screen is glitching.”
If the Chromebook is under warranty, check the manufacturer’s repair terms before opening it yourself.
Questions about a glitching Chromebook display
Why is my Chromebook screen flickering but everything still works?
The Chromebook can continue running while the display flickers. The cause may be a temporary ChromeOS graphics problem, an app, the built-in screen, or its cable. A full restart and external-monitor comparison help narrow it down.
Can a Chromebook screen glitch after an update?
Yes, display problems can appear after software changes, although timing alone does not prove the update caused them. Restart, check for a newer ChromeOS update, and test whether the issue affects the sign-in screen and an external monitor.
Why does the screen go black when I move the lid?
A fault that consistently follows lid movement can indicate a damaged or loose display cable near the hinge. Stop forcing the hinge and arrange an inspection. A software reset is unlikely to fix a physical connection.
Can I fix Chromebook screen lines without replacing the display?
Sometimes. Lines caused by a temporary graphics problem may disappear after restarting or updating ChromeOS. Fixed lines on the built-in panel, especially with a clean external display, may require cable or panel repair.
The key is to separate what ChromeOS is drawing from what the physical screen is showing. An external-monitor comparison, a screenshot checked on another device, and a careful lid test can prevent unnecessary resets and help you decide whether to keep troubleshooting or seek repair.
