One of the worst things that can happen when you sit behind your computer ready to work is a black screen.
Maybe you see some error messages like “No Input”, “Cable Not Connected”, “Check Video Cable”, or “No Signal”.
All of these are indicators that your motherboard or system isn’t detecting the monitor correctly.
There are various culprits for such an issue, from a minor software or hardware defect to a broken monitor or motherboard.
The best way to find the cause is by troubleshooting the system step by step, and that’s what this article will guide you through.
1. Monitor Issues
We need first to verify that the monitor is working correctly.
Start by determining if your monitor has power.
Look for a blue, green, orange, or red light on the monitor’s front, bottom, or back.
If you can’t detect a working light, no power is reaching the monitor.
Check the wall outlet first and ensure it’s working by plugging in a lamp or something similar.
Next, check if the monitor’s power cable is removable, and if so, swap it for another cable.
If you can’t remove it, check for any visible signs of damage instead.
The power might be cut out, and you’ll have to get a professional to exchange the cable.
If the lights didn’t come back on after verifying that the cable and outlet are working correctly, there might be internal damage to the monitor due to a circuitry failure.
The best way to check that is by replacing the monitor with a known working one.
If you don’t have a spare around, you can use your TV as a monitor.
Getting a signal indicates that the monitor has an internal issue.
Remember that having a monitor repaired isn’t always an economical option.
Do some research and make sure that replacing your monitor will cost you less in the long run before making the final decision.
2. Faulty Connections
If your monitor’s lights are on but the screen is black, the data cable might be causing the issue.
Firstly, ensure the cable fits securely in both ports and hasn’t become loose over time.
Let’s remind everyone that if you have a dedicated graphics card, the data cable should be plugged into it instead of the motherboard’s HDMI port.
Next, inspect the cable for any sign of damage.
If the cable is old, swap it for a new one.
Older monitors use VGA cables, and new models utilize DVI or HDMI cables.
Check if the cables are in the correct port.
If you have a cable with a different type than you’re using now, try swapping them.
The cables you’re using should be of high quality.
The DisplayPort cables should be certified by VESA.
Ensure the HDMI cable supports the port’s version.
For instance, an Ultra-High-Speed HDMI cable is necessary for running a 4K display.
Moreover, if you’re using a display adapter, it may be faulty and interfere with the connection.
Also, check the adapter’s type and ensure that it supports the monitor’s configured resolution.
Lastly, make sure that you’ve selected the correct input source of your computer.
The wrong input source can give you the “No signal” error message.
Open the Display menu by pressing the menu button on the edge of the monitor.
Look for Input Source and select the correct one.
For instance, if you’re using an HDMI cable, set the input as HDMI.
3. UPS Or Surge Protector Issues
A defective UPS or a faulty surge protector might cause the monitor not to get any signal.
If you’re using one of the devices, disconnect it and connect the computer directly into the wall outlet.
If this action gets the monitor up and running, the surge protector is broken, or the UPS may have a power defect or be overloaded.
Update its software and don’t connect multiple devices to the UPS at once.
4. Troublesome Peripherals
If you’re experiencing a completely black screen without any error codes, one of the peripherals might be the cause.
If any of the peripherals or extra connected hardware gets broken, this issue can happen.
Your computer only needs a motherboard, CPU, RAM, and Power Supply to function.
Turn off your PC and start disconnecting the mouse, keyboard, printer, scanner, and other external USB devices.
Then turn on the computer and see if the issue is fixed.
If so, reinstall each device one after the other and try turning on your computer again until you find the faulty one.
If the previous step didn’t help, disconnect the hard drive, SSD, DVD ROM, case lights, and other external devices.
Check again and repeat the same steps to find the defective part.
5. Wrong Boot Order
Sometimes, the black screen you’re seeing isn’t because of the motherboard not detecting the monitor, but because your PC is trying to boot from the wrong hard drive.
When it can’t find the OS there, it’ll give you the black screen.
To solve the issue, enter the BIOS.
Every computer has a different way of entering this interface, depending on its model.
You need to turn the PC on and press one of the following keys when it’s starting up:
You can check the computer or motherboard manual to find the correct key or search up your PC model on the internet.
When you’re in the BIOS interface, look for the Boot Order option and ensure the correct hard drive is at the top of the list.
Save the settings, exit, and reboot the system.
6. BIOS Settings
If you have wrongly configured a setting in the BIOS, it may be causing the black screen.
Restoring the BIOS to its factory settings may solve the issue.
- First, you should enter the BIOS as explained in the previous section.
- Once there, hit the F9 or F5 key to see the Load Default Options section.
- A Window should pop up at the bottom of the screen, asking you, “Load Optimal Defaults?” Answer: Yes.
- If you can’t see the mentioned option, go to the Security tab and find a menu for resetting the BIOS there.
It might have different names for different systems.
- If you can’t find any of the mentioned sections, click on the Exit link.
- The interface will display various options, including discard and restart, load defaults, save settings and restart, and so on.
- Select the Load Defaults option or a similar menu to reset the BIOS.
- Save before you exit.
It’s also possible to reset the BIOS by removing the CMOS battery:
- Turn off your PC and disconnect its power cable.
- Open up the case and find the CMOS battery on the motherboard.
It’s a round silver battery, usually on the right side of the motherboard.
- Remove the battery carefully, wait about a minute, and reseat it.
- Connect the power cord and check if the issue persists.
7. Multi-Monitor Issues
You may be trying to connect a second monitor to your computer or laptop, and one of them is getting the black screen.
In that case, first, make sure your PC can support running two monitors simultaneously.
Many PCs and laptops can only run one external display at a time.
Then go through the same troubleshooting steps mentioned at the beginning of the article, including checking the monitor for defects and making sure all the connections are correct.
If you’re connecting one monitor to the graphics card display port and the second one to the motherboard’s port, you’ll have to set the motherboard as your primary display adapter in the BIOS settings.
This way, both your GPU and motherboard will be active at the same time.
Next, head to Settings, select System, and then Display on your working monitor.
Find the Multiple Display section and hit the Detect button.
Also, undo any settings indicating a display on the main screen only and adjust it to mirror or extend the desktop on both displays.
8. Software Issues
To determine if software issues are causing the display problems, you should boot into Safe Mode and see if you get a proper image on the monitor.
A corrupted file or app, a virus, a faulty driver, or some wrong settings may be causing the problems.
To boot into safe mode, you’ll have to interrupt the startup process three times.
You can do this by pressing the restart button when Windows is booting up.
The system will take you to the Automatic Repair menu.
From there, head to the Advanced Options section to find Safe Mode.
If you’ve successfully entered safe mode, uninstall any apps and programs you’ve downloaded recently.
Also, uninstall any apps you suspect are causing the issue.
Next, you’ll have to ensure there aren’t any corrupt system files.
Run the Windows built-in tool for scanning and repairing the corrupted files:
- Type “Command Prompt” in the Windows search bar and open the app.
- Type “sfc /scannow” in the window that opens up and hit Enter.
- Wait for the command to complete and check the results.
You can also use a third-party tool for repairing corrupted files.
Reimage is a powerful utility, and here’s how to use it:
- Once you’ve downloaded and installed the app, launch it.
- Run a free scan and go through the detailed report the app provides afterward.
- If the app has detected any issues, you’ll have to purchase the full version to hit the Start Repair button and solve them.
It comes with a 60-day money-back guarantee.
Virus Or Malware
Different viruses and malware work in different corruptive ways, and messing with your display is one of them.
Running a trusted antivirus and scanning your system for threats couldn’t hurt.
If you have an antivirus program installed, make sure it’s updated.
If you’re using Windows antivirus and firewall, make sure Windows is updated to its latest version.
If you suspect that your PC is infected, you can restore your computer to a previous working state using the Windows System Restore function.
Faulty, incomplete, or outdated graphics drivers can cause the no display issue for your monitor.
Windows updates should install newer versions of drivers automatically, but it’s best if you download them on your own in this situation.
A. Task Manager
- Right-click on the Windows logo and select Device Manager from the menu.
- Find the Display Adapter heading in the list, double-click on it, and locate your GPU driver underneath.
- Right-click on the driver’s name and choose Update Driver.
- In the window that opens up, choose “Search automatically for updated driver software.”
B. Manufacturer’s Website
You can download and install them easily, but before doing that, it’s wise to uninstall the old graphic drivers using the DDU utility (Display Driver Uninstaller) to remove the remaining parts from the old drivers that can create issues.
C. Third-Party Tools
You can use one of the utilities made for locating and updating outdated or corrupt drivers automatically.
Working with them is easy and reduces the risk of installing the wrong driver.
Driver Easy is one of the best tools around for the task, and here’s how you can use it:
- Download, install and launch Driver Easy.
- Hit the Scan Now button for the app to scan your system and detect all the problem drivers.
- Once the list of drivers comes up, locate the GPU driver, and hit the Update button next to it.
- If you get the Pro version of the app, you’ll be able to update all your problematic drivers by hitting the Update All button.
If you’ve tweaked the display resolution and refresh rate before and set it to a higher state than your monitor can support, you’ll end up getting the “No Signal” error code.
Once you boot into safe mode, the system will start at a low resolution by default.
Follow these steps to fix the issue:
- Open Settings and choose System.
- Select Display and look for Display Resolutions.
- Click the downward arrow and select the option that has “Recommended” written next to it.
- Select Keep Changes in the pop-up window.
9. Hardware Issues
The cause for your monitor not getting a signal could be a failing hardware component.
The two components most likely to cause display issues are the graphics card and the RAM sticks.
Unplug your PC and open up the case.
Inspect the RAM and GPU and ensure they’re not loose.
Take them out gently and reseat them.
Look for any signs of damage on the RAM sticks and graphics card and have them repaired if you see any.
You can remove them and try starting up your PC.
If the display is fine, then you know the components are defective.
10. Motherboard Issues
If you’ve determined that the other components weren’t causing the issue, the only remaining culprit is a defective motherboard.
You could open the case and run some tests yourself to determine if your motherboard has a problem.
First, check the HDMI port on the motherboard for any signs of damage.
If the HDMI port is damaged, you’ll have to get it replaced.
Next, have a visual check and look for a blown, bulging, or leaking capacitor.
If you find one, that’s what’s causing the issue, and it should be replaced immediately.
These aren’t cheap tools, but you might consider purchasing them.
It’s always wise and easy to get help from a technician, especially for motherboard issues.