Start with the simplest fixes first

A blank, flickering, or discolored screen usually comes from one of three places: a loose cable, a wrong display setting, or a hardware problem. Before you assume the screen itself is broken, check the physical connections and your computer's display settings. Most screen problems can be fixed in under five minutes without opening the computer or buying parts.

The order matters. Always start by checking cables, then restart your computer, then adjust settings. Only after those three steps should you consider that the monitor or graphics card needs repair.

Key Takeaways

  • Check that the monitor power cable and video cable are fully plugged in at both ends, and that the power button on the monitor itself is turned on.
  • Restart your computer completely — turn it off, wait 10 seconds, then turn it back on — because many display problems clear on their own during startup.
  • If you see a picture on an external monitor but not your laptop screen, the laptop display may have been disabled in settings or by a keyboard shortcut.
  • Flickering, color problems, and resolution issues usually come from display settings or outdated graphics drivers, not from a broken screen.
  • If the screen stays completely black even after restarting and checking cables, the graphics card or monitor may need professional repair.

Check all the cables and power

Unplug the monitor power cable from the wall outlet, wait 10 seconds, and plug it back in. This resets the monitor's internal electronics and fixes many display problems. While the monitor is unplugging, look at the back of the monitor where the video cable connects — on a desktop computer, this is usually a cable labeled HDMI, DisplayPort, or VGA. Make sure it is fully seated in both the monitor and the computer. A cable that looks plugged in but is actually half an inch loose will produce a black screen or no signal message.

On a laptop, there is no external monitor cable to check, but make sure the laptop is plugged into power. A laptop screen that dims or goes black sometimes does so because the battery is low and the computer is trying to save power. Plug in the AC adapter and wait 30 seconds.

If you are using an external monitor with a laptop, check that the video cable is connected to the correct port on the laptop. Many laptops have multiple video ports — HDMI, USB-C, or Thunderbolt — and the computer may not automatically detect a monitor plugged into the wrong one.

Restart your computer completely

Turn off your computer entirely using the power button or the shutdown menu. Wait 10 full seconds — do not skip this step, because the monitor needs time to fully power down. Then turn the computer back on. During startup, watch the monitor for any sign of life: a logo, a loading bar, or text. If you see anything, the monitor is working and the problem is in the display settings.

If the screen stays completely black even during startup, and you hear the computer fan running and see lights on the computer case, the graphics card or monitor cable may be damaged. Try the next section before assuming hardware failure.

Check display settings on Windows

Right-click on the desktop and select Display settings. Look at the resolution setting — if it is set much higher or lower than what your monitor supports, the screen may show a distorted or blank image. Set the resolution to the recommended value, which Windows usually shows in parentheses next to the current setting.

If you cannot see the desktop to right-click, use the keyboard shortcut Windows key + I to open Settings, then navigate to System > Display. You can also press Windows key + P to open the quick display menu, which lets you switch between your laptop screen, an external monitor, or both without opening full settings.

Check whether your monitor is listed under "Advanced display settings." If an external monitor is plugged in but does not appear in the list, Windows may not recognize it. Unplug the video cable, wait 5 seconds, and plug it back in. Windows will scan for new displays.

Check display settings on Mac

Click the Apple menu, select System Settings, then go to Displays. If you have an external monitor connected, it should appear as a separate display in this menu. If it does not appear, try unplugging the video cable and plugging it back in — macOS will detect it within a few seconds.

Check the resolution setting. If it is set to a value your monitor does not support, the screen may go black or show a "no signal" message. Select the resolution marked "Recommended" to match your monitor's native resolution.

If your laptop screen is black but an external monitor works, your laptop display may have been disabled. Go to Displays settings and check whether your laptop screen is listed. If it is not, click the dropdown menu next to "Arrangement" and make sure your laptop display is not unchecked.

Update your graphics driver

Outdated or corrupted graphics drivers often cause flickering, color problems, or resolution issues. On Windows, right-click the Start button, select Device Manager, and expand the "Display adapters" section. Right-click your graphics card — it usually says Intel, NVIDIA, or AMD — and select Update driver. Choose "Search automatically for updated driver software" and let Windows read and install the latest version.

On Mac, graphics drivers update automatically through System Settings > General > Software Update. Check for updates and install any available. After updating a driver on either system, restart your computer.

If updating the driver does not fix the problem, try uninstalling it and letting your computer reinstall the default version. In Device Manager on Windows, right-click the graphics card and select Uninstall device. Restart your computer, and Windows will reinstall the basic driver automatically.

Try a different cable or monitor

If you have access to another video cable or monitor, test with it. Borrow an HDMI cable from a friend or use a different monitor at work. If the screen works with a different cable or monitor, the original cable or monitor is faulty and needs replacement. If the problem persists with both, the graphics card or computer motherboard may be damaged.

On a laptop, you cannot easily swap the built-in screen, but you can test by connecting an external monitor. If an external monitor works but the laptop screen does not, the laptop display itself is likely broken and requires professional repair. If neither the laptop screen nor an external monitor displays anything, the graphics card may be the problem.

When to seek professional repair

If the screen remains completely black after restarting, checking cables, and adjusting display settings, the graphics card, monitor, or motherboard may need repair. Take your computer to a repair shop or contact the manufacturer's support line. Bring a list of what you have already tried — this helps the technician narrow down the problem.

If the screen flickers constantly even after updating drivers, or if colors are severely distorted and do not improve with settings changes, the monitor itself may be failing. Monitor repair is usually not worth the cost; replacement is often cheaper.

Frequently Asked Questions

Why does my screen go black when I move my laptop?

A loose video cable inside the laptop can disconnect when the screen is moved or tilted. This is a hardware problem that requires opening the laptop or taking it to a repair shop. In the meantime, try keeping the screen at a fixed angle and avoid moving it.

My monitor says "no signal" but the computer is on. What do I do?

Unplug the video cable from both the monitor and the computer, wait 10 seconds, and plug it back in firmly. If that does not work, try a different video cable or a different port on the computer. If a different cable works, the original cable is faulty.

Can I fix a cracked monitor screen myself?

No. A cracked LCD screen cannot be repaired at home — the liquid crystal layer is sealed inside and cannot be accessed without destroying the monitor. Replacement is the only option. Check whether your monitor is still under warranty before buying a new one.

Why is my screen flickering even though it was working fine yesterday?

Flickering usually comes from a loose cable, an outdated driver, or electromagnetic interference from nearby devices. Check the video cable first, then update your graphics driver. If flickering continues, try moving the monitor away from wireless routers, microwaves, or other electronics that emit radio signals.

My laptop screen is dimmer than it used to be. Is it broken?

Probably not. Check your brightness settings — press the brightness keys on your keyboard (usually marked with sun symbols) or go to Display settings and increase the brightness slider. If brightness is already at maximum and the screen is still dim, the backlight may be failing, which requires professional repair.