Your coffee is brewed. Your mind is sharp. You go to turn on your computer, but nothing shows up—all you see is a black screen, with no explanation as to where all your precious memes of the day are hiding.
A blank screen is a bit difficult to diagnose, since so many things can cause it—your entire computer could be malfunctioning, or it could just be the monitor. Maybe you get a message like “No Input” and “Cable Not Connected,” or maybe it’s just a completely black screen. Let’s walk through some troubleshooting steps so you can get back to working hard (or wasting time) on the internet.
Have You Tried Turning It Off and
On Again?
This may sound obvious, but make sure your computer and monitor are actually powered on. Both should have lights on the front that brighten up when receiving power, and it’s completely possible you bumped the monitor’s power button at some point without realizing it.
If your computer is on, try rebooting it, and see if the problem persists. Press the menu button on your display to make sure it’s on the correct input, as well. (Most should auto-detect the correct input, but it never hurts to double-check.)
Also make sure your brightness is turned up. Many laptops let you dim the screen down to nothing, so raise the brightness and you might find your computer was running properly this whole time—it was just dimmed.
Similarly, try holding the function key and pressing any button that looks like a computer display along the top of your keyboard—the screen may have been disabled, or gotten confused after being disconnected from an external monitor.
Finally, you might even try unplugging the monitor entirely. I’ve owned a display that, when stuck on an input with no connection, would refuse to show a picture until I unplugged it. If your monitor is stuck on an input with nothing plugged in, you may even need to plug something into that port before you can switch inputs to the correct one. It’s rare, but it happens.
Check Your Connections
Next, make sure no cables have come loose. In particular, ensure your monitor is plugged into the wall and receiving power, and double-check that the cable going to your PC is firmly plugged in at both ends.
If you have a graphics card, your monitor should be plugged into that, not the HDMI port on your motherboard. If you have any extra cables lying around, try another one—maybe the cable you’ve been using is damaged, or one of the ports is malfunctioning. (If you have a cable of a different type—say, an HDMI cable instead of a DisplayPort cable—try that, too.)
In addition, make sure your cable has the right specs for the job: if you’re using DisplayPort, make sure it’s certified by VESA, and if you’re using HDMI, it may have a certification label on the packaging you can scan with the HDMI Cable Certification app for iPhone or Android. Remember, not all cables are created equal: if you’re trying to run a 4K display at a high refresh rate, for example, you’ll need an Ultra High Speed HDMI cable, rather than an older High Speed model. You can read more about cable ratings in our guide.
If you’re using any adapters, those could be the culprit as well—either you have a faulty dongle, or you’re using it in a way it wasn’t intended to be used. HDMI to VGA adapters, for example, only work in that direction—if you’re trying to hook a VGA computer to a DVI monitor, you’ll need a different type of active converter.
While you’re fumbling around with cables, unplug anything from your computer that isn’t essential (i.e. the mouse, keyboard, and monitor). I’ve had situations where a specific USB port would prevent the computer from booting if something was plugged into it—weird, but it does happen. (You might even try moving your mouse or keyboard to another port, just to be super-duper sure.)
Multi-Monitor Matters
If you’re trying to hook up a second monitor, whether to a laptop or a desktop, you may run into issues where only one of the screens works properly. First, make sure your laptop or computer is capable of running two or more displays at once—some machines may not support all the monitors you want to connect. (The latest M1 MacBooks, for all their improvements, only support one external display at a time, for example.)
Next, once you’ve plugged in your second monitor, go to Settings > System > Display. If your second display is recognized by the system but showing a black screen, it may be a result of the settings on this page—you may have it set to only show a picture on the laptop screen, for example, and can adjust this to mirror the desktop on both displays or extend the desktop across both displays.
Listen for the Beep
When your computer boots up, you’ll usually hear a small beep from a speaker that lives inside the tower. This speaker exists to give you error codes when something goes wrong. If you don’t have one, you can order one on Amazon and plug it into the speaker header on your motherboard.
If your PC just makes a quick beeping noise when it boots, then it isn’t registering any hardware problems. But if it makes a specific sequence of beeps—say, one long beep, then two short beeps—it’s trying to tell you something. It could be a failing stick of RAM, a CPU that’s overheating, or a video card that isn’t seated properly. (Other machines may have a digital display that shows error codes instead of beeps, or a series of lights that turn on in a specific order to indicate a problem.)
There are web pages with information on these beep codes, but your best bet is to look at the manual for your specific PC or motherboard, as it’ll be most accurate. Once you figure out the problem, fixing it should be a piece of cake.
Fix Your Boot Order
Occasionally, your PC may try to boot from the wrong hard drive—and when it doesn’t find an operating system, it will just give you a black screen (sometimes with a blinking cursor in the corner). This is easy to fix.
Reboot your computer and enter the BIOS setup menu, usually by pressing a key like DEL or F2 as it boots. From the BIOS menu, look for the Boot Order option, and make sure the correct hard drive is at the top of the list. Then save your settings and exit. If you’re lucky, you’ll reboot into Windows.
If that doesn’t work, you can also try loading Optimized Defaults from the BIOS. If you’ve misconfigured something else in the past, this will bring you back to the default settings, which may allow you to boot. (Though I recommend taking a picture of your BIOS settings first, in case you actually need something other than the default to boot properly. That way, you can put everything back if resetting the defaults doesn’t work.)
Reseat Your Graphics Card, RAM, or Other Hardware
If you recently built, upgraded, or moved your desktop computer, it’s possible a piece of hardware came loose inside the case and is preventing the computer from booting. Remove the side panel from your PC and look inside. If you have a graphics card, try removing it and re-inserting it into its PCIe slot until it clicks—or try moving it to a different slot entirely. Make sure its power cables are firmly locked in place as well.
While you’re inside, reseat the RAM sticks as well, pressing down on the levers near the edges to pop the stick out of its slot, then pressing it back in until you hear the latches click. Make sure all the cables connected to the motherboard are plugged in all the way snug, and that your hard drive is connected.
Buckle Up for Safe Mode
If you still can’t see a picture when your computer boots, you may have a driver or other software issue. You might be able to get a picture if you boot into Safe Mode, though doing so is a bit difficult if you don’t have a working screen to begin with.
You have a couple of choices: if you interrupt the startup process three times (by pressing the restart button as Windows begins booting, for example), you’ll be dumped into the Automatic Repair menu, where you can go to Advanced Options to find Safe Mode.
If you can’t get that to work, you can also create a Windows 10 installation drive using another PC, boot from that flash drive, then head to Repair Your Computer > Troubleshoot > Startup Settings to choose Safe Mode with Networking.
If your computer boots into Safe Mode, there’s still a chance of fixing things up. Try uninstalling any new programs you have that may be causing a problem. Make sure your resolution and refresh rate are set properly (if you had them set too high, your monitor might not be able to display a screen).
You can also try reinstalling your graphics card drivers by downloading them from the manufacturer’s website. If you have any leftover graphics drivers on your system, you can fully clean them by running Display Driver Uninstaller. This tool is not for the faint of heart, but it’s the only way to truly wipe every trace of a graphics driver from the system, which can sometimes cause problems.
You might even want to run a malware scan while you’re in there, use System Restore, or even a recovery drive (if you have one) to roll back to a known working configuration. Once you’re done with that, see if your computer will reboot normally.
If not, you can head back to that troubleshooting menu and try the Startup Repair option. You might also head to the Command Prompt and run sfc /scannow or chkdsk C: /r to check for drive errors—if you’re lucky, Windows will be able to repair any problems and get you booting again.
Try Another Video Card or Monitor
If none of the above solutions fix the problem, you may have to do some more in-depth testing with some spare hardware, if you can get your hands on some. Find a cheap video card on Craigslist and see if it works in place of your current card—if so, the problem may be with your GPU, and it’s time to upgrade.
See if your computer will boot when plugged into another monitor or your TV. If you’re using a laptop, plug into an external monitor to see if the problem is your display or the PC itself. If your display is malfunctioning, you may be able to replace the LCD panel in your monitor or laptop yourself (if you’re handy with a screwdriver). Otherwise, it may be time to call in the professionals—hopefully you have a good backup in case they have to wipe the drive.
