This article will show you how to connect two monitors to one desktop computer. This can be done on a Windows computer and Mac OS X, but in the case of Windows, you need a computer with a video card that supports multiple monitors.
Method 1 of 2: On Windows
Step 1. Make sure you can connect multiple monitors to your computer
Locate at least two horizontal connectors on the back of the computer case (at the bottom of the panel); these connectors are found on the video card and are used to connect two monitors.
- Note that two monitors cannot be connected to the video connector on your motherboard (this is the vertical connector at the top of the back of your computer case).
- Remember, the vertical connectors belong to the motherboard, and the horizontal connectors belong to the graphics card.
- If there are no described connectors on the rear panel of the case, install a video card.
Step 2. Find out what video connectors are on the video card and monitors
To do this, look at the video card connectors and monitor connectors to determine their type:
- DVI - wide plastic connector with numerous square holes;
- VGA - multi-hole trapezoidal color plastic connector;
- HDMI - Slim Hexagonal Connector;
- DisplayPort - Similar to an HDMI connector, but with one edge cut off rather than symmetrical to the other. Required to connect 4K monitors;
- Thunderbolt - This connector is found on the back of most iMac monitors. marked with a lightning bolt icon. An adapter (for example, VGA-Thunderbolt) can be connected to this connector, with which you can connect to any of the above connectors.
Step 3. Buy the required cables (if not available)
If, for example, a DisplayPort cable is connected to the video card connectors, buy one for each monitor.
If your monitors and graphics card have different connectors, buy an adapter or cable with two different plugs (for example, DisplayPort on one end and HDMI on the other)
Step 4. Turn off your computer
This will make it easier to connect a second monitor and avoid problems.
Step 5. Connect the first monitor to one of the video card connectors
If the first monitor is connected to the vertical video connector on the motherboard, disconnect the cable and connect it to the horizontal video connector.
If the video connector on the motherboard is different from the connectors on the video card, use a different cable
Step 6. Connect a second monitor
Connect the second monitor cable to a different connector on the video card.
Step 7. Connect the second monitor to a power source (wall outlet)
Do this with the supplied power cable.
Step 8. Turn on your computer and monitors
Press the power buttons on the computer and on each monitor.
Step 9. Open the Start Menu
Click on the Windows logo in the lower left corner of the first monitor screen.
Step 10. Open "Options"
Click the gear-shaped icon at the bottom left of the Start menu.
Step 11. Click on System
It's a monitor-shaped icon in the Options window.
Step 12. Click the Display tab
You will find it in the upper left side of the window.
Step 13. Open the drop-down menu "Multiple screens"
It's at the bottom of the window.
You may have to scroll down the page to find this menu
Step 14. Select the required option
Select one of the following options from the drop-down menu:
- Duplicate these screens - the same picture will be displayed on both monitors;
- Expand these screens - the picture will be stretched across two monitors;
- Show desktop to 1 only: the picture will be displayed only on the first monitor;
- Show desktop only 2: The picture will be displayed on the second monitor only.
Step 15. Click Apply
This button is at the bottom of the window. The second monitor will display part or all of the picture that you see on the first monitor (depending on the option you selected).
Step 16. Click Save Changes when prompted
The changes made will be saved. Now, along with the first monitor, you can use the second.
Method 2 of 2: On Mac OS X
Step 1. Find out which cable you need
To connect a second monitor to your iMac, you need a cable that matches the connector on the back of your iMac monitor. Locate one of the following connectors on the back of your iMac:
- Thunderbolt is a small, square connector that is marked with a lightning bolt icon. Plugging a cable into two Thunderbolt connectors is the easiest way to connect two Mac monitors to each other. If necessary, purchase an adapter for any other video connector (for example, a Thunderbolt to VGA adapter).
- HDMI is a slim hexagonal connector. HDMI is a common connector for connecting audio and video equipment, so it can be found on most monitors.
Step 2. Buy the required cables (if not available)
If you need an HDMI cable to connect a second monitor, for example, buy one.
If you bought a monitor with outdated connectors (such as a VGA connector), buy a Thunderbolt to Connector or HDMI to Connector adapter (such as Thunderbolt to VGA)
Step 3. Connect the second monitor cable to the back of your iMac
If you are using an adapter, first connect it to the indicated connector.
Step 4. Connect the second monitor to a power source
Connect the power cord that came with your monitor to a power source (wall outlet).
Step 5. Turn on the second monitor
To do this, press the power button on the second monitor. The desktop should appear on the screen.
Step 6. Open the Apple menu
Click on the Apple logo in the upper left corner of the main screen. A dropdown menu will open.
Step 7. Click System Preferences
It's near the bottom of the drop-down menu.
Step 8. Click on Monitors
This monitor-shaped icon is located in the System Preferences window.
Step 9. Click the Layout tab
It's at the top of the Monitors window.
Step 10. Choose how the picture will be displayed on the monitors
If you want the picture to be stretched across both monitors, uncheck the "Enable video mirroring of monitors" option; if you want the same picture to be displayed on each of the monitors, leave the checkbox next to the specified option.
Step 11. If necessary, move the menu bar
To display the menu bar (the gray bar at the top of the screen) on the second monitor, drag the white rectangle that is at the top of one of the blue monitors to the second monitor.
Step 12. Close the "System Preferences" window
Close the Monitors window and the System Preferences window. Now, along with the first monitor, you can use the second.