By John Woram
(February 4, 2005)

Adding a second monitor to your PC just doesn't make sense--until you try it. With two monitors, you can view a spreadsheet and write a report without constant minimizing and maximizing. Editing photos? Keep your tools on the secondary screen so that you can better view your image. Troubleshooting a software problem? Keep the instructions on one screen while performing the steps on the other. Finally, stretch that wide spreadsheet across two monitors for a bird's-eye view of all the numbers. Just find your spare monitor (or some spare cash) and some extra desk space, and we'll show you how to start seeing double.

Add a second monitor to your PC

Before you get started with this project, we recommend that you have the following:

Add a second monitor to your PC

If you've replaced an old monitor, chances are it's still sitting at the bottom of a closet somewhere. Otherwise, you'll need to head to the store for a new one, but it needn't be a budget buster. Remember, we're talking secondary here, so the addition doesn't have to match the performance or size of your primary monitor. In fact, if you're creating files that others will view, having monitors of different sizes and resolutions will give you a better idea of what your work may look like on other screens. If you're ready for a new monitor anyway, this is the perfect excuse to buy a bigger, better one and let the existing model take on secondary status.

Add a second monitor to your PC

If your graphics card has two outputs--the older analog port and the newer Digital Visual Interface (DVI) port--all you have to do to connect a second monitor is plug it into the available port. Newer LCD monitors probably have a DVI port, and that's the one you should make the primary monitor because the picture will be better.

If your graphics card has only one output, you have two choices: You can replace it with a card with two outputs, or you can buy a secondary PCI graphics card, provided you have a free PCI slot. Today, most cards connect via your motherboard's AGP slot. A PCI card may be a cheaper option, but it will be slower--and that's if you can even find one in retail stores, especially one with much more than 64MB of memory, which you would need for heavy gaming or graphics-intensive work on the monitor connected to this card. Opting for a dual-input AGP card gives you the benefits of AGP on both monitors, more video memory, and one higher-quality DVI port.

If you don't have a graphics card and are relying on integrated graphics instead, you'll need a standalone graphics card. If that's the case, you should look for one with two outputs, because when you plug in the new card, the integrated output is usually disabled. Some newer PCs have the faster PCI Express (PCIe) card slots; the x16 slot is for your graphics card. If you're buying a card for this slot, make sure it's a PCIe card.

Add a second monitor to your PC

Now that you've worked out the graphics-card conundrum, connect the secondary monitor. If your card or combination of cards includes a DVI port, you'll probably want to connect the primary monitor to the DVI port and the secondary monitor to the analog port. Some monitors have dual analog and digital inputs and can take advantage of whatever output is available. If neither monitor has a DVI port, don't worry. You can buy an inexpensive adapter that enables you to connect it to your PC's DVI port. It will still be an analog signal, however.

As a quick recap, analog connectors have three staggered rows of five pins each, while digital connectors have three uniform rows of eight pins each, with an additional four-pin-plus-blade connector arranged in a square.

Add a second monitor to your PC

The next step is to turn on both monitors and boot the PC. Depending on your PC's configuration, you may see activity on both screens during start-up. When the Windows desktop appears, right-click in any empty space to open the Display Properties dialog box, then select the Settings tab. You should see two blue rectangles, labeled "1" and "2," with a dotted border surrounding the latter, indicating the second monitor is still not active. Move your mouse over the monitor 2 rectangle, and a Not Active tool tip should appear. Right-click and check the Attached option to activate the secondary monitor.

Now set the resolution and color quality as desired and check the box labeled "Extend my Windows desktop onto this monitor." Then drag the monitor 2 rectangle so that the positions of the two rectangles in the dialog box match the physical positions of the two monitors. You can place monitor 2 above, below, or on either side of monitor 1, and with the virtual and physical positions in agreement, you can drag the mouse from one monitor to the other, just as if the two monitors were one large screen.

Before you quit the Display Properties dialog box, click the Identify button to display a large number on each monitor, which should agree with the number placement seen in the dialog box.

Add a second monitor to your PC

With both monitors up and running, you can now view two documents in their entirety at the same time, drag icons and toolbars from one window to the other, and edit images without having toolbars take up half your screen.

You may see a few quirks, however. As you make various configuration changes, be prepared for Windows XP to rearrange the icons on your desktop, probably lining all of them along the left side of the primary monitor screen. You'll just have to put up with this positioning and relocate them as desired once you're done.

If a browser running on the secondary monitor opens a new window, that window may show up on the primary monitor. Or if the new window is supposed to appear at a specified location, it may instead butt against the side that's closest to the primary monitor.

If the secondary monitor is smaller than the primary monitor, the title bar of a window may be off the top of the screen, making its menu bar and other items inaccessible. If so, just drag the side of the window nearest the primary monitor back over to that monitor, thus exposing part of the title bar, which you can now drag as needed. If this is a recurring problem, go back to the Display Properties dialog box, select the Settings tab, and drag the top of monitor 2 up to align it with the top of monitor 1.

Once you've worked out any kinks, you'll quickly appreciate the benefits of a dual-monitor setup and wonder how you ever survived with only one screen.