How to Set Up Dual Screens for a Computer

By Darla Ferrara

Installing a second monitor to your computer has advantages. In most situations, an additional computer screen will double desktop space. This allows you to multi-task using just one hard drive. A second monitor does not need to be fancy. The display can be an old CRT unit, an LCD screen, even the right television might work. Your computer does need to have the correct hardware. You must have either two video graphics cards or one card with dual ports. With the correct hardware, the operating system set-up is straightforward.

Connect the Second Monitor

Step 1

Turn your computer off.

Step 2

Turn the second monitor around and look for a cable. One end will be embedded in the monitor. The other end will have a 15-pin video connection. This is a VGA cable.

Step 3

Look on the back of your computer for a corresponding port. Most video connections will have an icon of a monitor below the port. Your computer will have two VGA ports that correspond to the connection from a monitor. Your current monitor will be attached to one, the second should be open.

Step 4

Slide the open end of the cable from the second monitor onto the open port on the computer. It will only fit in one direction because of the shape. If the connection does not attach, turn it over and try again.

Step 5

Use a screwdriver or your fingers to tighten the screws on each side of the cable connection once the cable and port are securely seated.

Step 6

Turn the monitor on and boot your computer.

Windows XP

Step 1

Follow the on-screen instructions while the operating system recognizes the new monitor.

Step 2

Right-click on any empty space on your computer desktop and select "Properties" from the menu options next to your cursor. This will open the "Display Properties" dialog box.

Step 3

Navigate to the "Settings" tab at the top of the "Display Properties" window.

Step 4

Move to the display list and select your second monitor from the options.

Step 5

Click on the box next to "Extend my Windows Desktop onto this Monitor" and press the "OK" button.

Windows Vista

Step 1

Wait for Vista to recognizes the second monitor, a "New Display Detected" window will appear on the first screen.

Step 2

Select the option that works for your situation. "Mirrored" will present your desktop on both monitors. "Extended" increases desktop space using both monitors. "External display" only works well for presentations or for watching a movie on one unit.

Step 3

Click the "OK" button at the bottom of the dialog to save your settings.

Windows 7

Step 1

Follow the on-screen instructions while the operating system recognizes the monitor.

Step 2

Click on the "Start" button at the bottom on the desktop (first monitor) and open the Control Panel.

Step 3

Double-click "Appearance and Personalization" and select "Adjust screen resolution."

Step 4

Move to the drop-down list next to "Multiple displays." Select "Extend these displays" from the list.

Step 5

Click on the "OK" button at the bottom of the dialog box.