PC doesn’t see second monitor: how to fix?

To get the best experience and improve productivity, users use one, two or even more monitors. This does not mean that you need to buy another computer or laptop to use two monitors.

If your video card supports multiple connection ports, then you can safely connect to it several monitors. Based on this, the number of monitors that you can connect to PC depends on the number of ports on your video card.

You can find various ports on the video card, for example, VGA, DVI, HDMI and Displayport. Nowadays, HDMI and Displayport are the most popular connection interfaces. VGA and DVI-I (not DVI-D), in turn, are almost no longer used (connecting a modern video card to a VGA-monitor and in general is incredibly problematic).

The most common connection interface is HDMI, which allows users to access the highest resolutions at the moment. Plus, HDMI can also transmit a signal from a sound card.

In addition to the various connection interfaces for video signal transmission from the video card to the monitor, there are two different types of video cards: integrated and discrete (PCIe). What is the difference between these two types of video cards?

The integrated graphics card is built into the motherboard, and the PCIe graphics card is connected to the PCIe slot of the PC motherboard. If you are playing video games, doing graphic design or editing video, we recommend that you use a discrete graphics card, as it is designed for such tasks and is much more productive.

Sometimes, you will need to connect a second monitor to your machine. This procedure is quite simple: take a cable with the desired connection interface, for example, HDMI, connect one end of it to the connector on the video card, and the other – to the connector on the monitor. That’s all.

However, sometimes things do not go so smoothly, and your computer, for whatever reason, can not detect a second monitor. What is the reason behind this trouble? So, there are many reasons: cable problems, incompatible drivers, computer configuration problems for the user, etc.

In this article, we will look at 10 different methods that we hope can help you with the problem of detecting a connected monitor.

Method # 1 Changes to the projection mode

If you correctly connected the monitor to your video card, but nothing is displayed on it, you can try changing the projection mode. The problem could arise simply because your video card did not know what to do with the second connected monitor. Now we show you how to change the projection mode to Windows 10. Although, the same can be done on operating systems such as Windows 8 and Windows 8.1.

• Press the keyboard shortcut Windows + P.
• Then you will see a menu for selecting the projection mode, in which there will be four settings. Select the setting according to your preferences and click on it.
• Well, the second monitor finally revived? If not, the point was not this and we move on.

Method # 2 Restart the computer

In the operating system Windows (as, indeed, in any other OS), sometimes there are various bugs and errors that prevent it from working correctly, and, as a result, prevent the user from using the OS functionality.

Try to reboot your machine to fix a possible problem. There is a possibility that the problem is on the side of your OS, which stubbornly does not want to find another monitor in the available devices. After reboot, try the method described above again.

Method # 3 Disabling the computer, monitors and cables

Ok, in the past method, we tried to simply reboot your computer to get rid of the possible “cant” OS Windows 10/8.1/8. However, perhaps the problem is not at the software level, but at the hardware level.

Try to completely disconnect your computer, disconnect all monitors from it, disconnect all cables from them. Also, do not forget to disconnect your two monitors from power. Wait for a couple of minutes, then reconnect all the equipment.

Perhaps in the connected equipment of your computer there was some kind of conflict and the second monitor refused to be detected by the system. This method helps some users on the network (at least some of them say so). Plus, there’s no risk in doing, say, this trick. So why not try it.

Method #4 Video adapter reconnection (video card)

Some users argue that they simply solved the problem with not displaying the second monitor by simply reconnecting the video card through the system utility “Device Manager”.

This is done very simply and now we will show you how to do it:

• Right-click Start and select Device Manager.
• Before you open a list of equipment that is installed and running on your system. Find the “Video adapters” section.
• Find the name of your video card in the list and right-click on it.
• Select “Disconnect Device”.
• Then right click on the driver from your video card and select “Enable device” again.
• Test your second monitor again.

Probably, your second monitor was not diligently detected because the driver for your video card started, for some reason, to malfunction. Such a simple procedure of reactivation a device can often correct the situation.

Method #5 Reinstalling monitors

Ok, if switching your video adapter does not help fix the situation, then let’s try to reinstall the monitors that are now connected to your system. Again, go to the System Utility Task Manager and follow these steps:

• In front of the list of installed equipment, find the “Monitors” section.
• Open this section and find your monitor in the list. Right-click on it and select “Delete Device.”
• After your monitor turns off, restart the computer and connect a second monitor to it, if it has not yet been connected to the system unit, and then the main monitor.
• Then check if your second monitor is displayed in conjunction with the main monitor.

Method # 6 Rollback driver to a previous version

Perhaps the problem with finding a second monitor is the driver for the video card that is currently installed in your system. To solve this problem, you can try to roll back the video driver to the previous version. This is done, again, through the Device Manager.

• Go to Device Manager, go to the Video adapters section and find your video card.
• Right-click on it and select Properties.
• Go to the “Driver” tab.
• Click on the “Rollback” button.
• As soon as the driver rolls back for your computer, try to connect two monitors to it again. If this time everything went fine and you did the same, the thing was definitely the driver for the video card.

Method #7 Changing the refresh rate

In this method, you and I will now try to change the refresh rate on your monitor, since it can cause problems when connecting a second monitor. For example, you could set the refresh rate to 75 Hertz on your main monitor, while on it, and on an additional monitor, the maximum refresh rate is 59-60 Hertz.

• Click on the Windows + I keyboard to go to the system settings.
• Go to the “System” section.
• Then select the “Display” tab.
• Go to the bottom of the window with the settings of the screen and click on the link “Properties of the graphics adapter.”
• Go to the “Monitor” tab.
• Click on the drop-down menu and select the correct refresh rate for your monitor, for example, 60 Hz.
• Apply the changes.
• After changing the refresh rate, try connecting a second monitor and see if something changes. You can also try to expose something in the projection settings, which we mentioned in the very first paragraph.

Method #8 Tricks for laptop owners

If you are trying to connect a second monitor to a laptop, then we can recommend you to do a couple of tricks, which may help when connecting a second monitor:

• Try to close your laptop when the monitor is connected (this will make the laptop display temporarily off). The second monitor should now be marked as the main monitor. As soon as you open the laptop, you should earn both displays at once.
• Try to enter the computer into hibernation mode while a second monitor is connected to your computer, and then bring it out of this mode.

Method #9 Activating multiple displays

If you are a user of a video card from Nvidia, then you can try to enable the option of multiple displays in the Nvidia Control Panel.

• Right-click on the desktop and select “Nvidia Control Panel”.
• Go to the “Display” section.
• Click on the “Install Multiple Displays” subsection.
• Check the box that is connected to your computer.
• Click “Save” and close the Nvidia Control Panel.
• Method number 10 Check the monitor, ports and cables

If you can not connect the second monitor to the computer (given that you know the procedure itself), then maybe something is wrong with the monitor itself, the connection ports or cables. Try to check these components, since the problem may be simply out of order equipment.

AuthorZac Turner