The whole picture: Extra monitors for PC and laptops

By Andreas Thieme Aug 1, 2010, 12:16 GMT

Munich - If your monitor's not giving you a broad enough view, simply expand it. A second display can be a big boon, with higher resolution and better image quality. In some cases it's even possible to add a third display to the computer. The extra monitor typically improves your working comfort.

'The second display enlarges the virtual workspace for the PC or laptop,' says Robert Kraft from computer portal chip.de. Multitasking suddenly becomes much easier: your can play back your vacation film on the second monitor while editing it on the first - without the annoying minimizing and maximizing of windows. The same applies to office tasks: you can keep a program like your email client permanently open on the second screen.

A study by Microsoft a few years ago showed that two monitors provides a more effective way to work. The boost comes through the so-called widescreen effect: the larger, multi-section image area simplifies working on the computer and increases productivity by ten per cent on average. The study found that once you use a second monitor, you'll never go back.

Another reason for picking up a second monitor is to achieve higher resolutions. 'That's particularly the case for laptops,' Robert Kraft observes. Monitors of 22 inches in size, with a resolution of 1920 by 1080 pixels or greater, are suitable for playing back HD films.

The cable for connecting display and computer usually comes delivered with the monitor. Additional hardware is only needed if the computer lacks a digital DVI, HDMI, or display port and the monitor does have one. The lowest common denominator is almost always the analog VGA port, which typically delivers worse image quality than a DVI port.

'If the cable doesn't have the right plug, then you'll need an adapter to convert a DVI or VGA signal,' Kraft explains. The adapters are also sometimes included with delivery. Software is not typically required.

In many cases long connection cables can lead to degradation of the picture data, Kraft explains. 'This results in jitters and skips, especially for film scenes with a lot of movement.' To prevent these artefacts, as they are known, the viewer should avoid cables longer than two metres. If you need to go beyond that, with five metres as an extreme, then a high quality cable should be purchased.

The operating system also plays a role with an external monitor, says Michael Schmelzle from Germany's PC Welt magazine. While Windows 7 and Vista identify the device automatically, Windows XP often requires additional graphic card drivers and a restart.

For cards from hardware maker ATI, the 'Desktops and Displays' panel includes an 'Identify displays' function, while Nvidia cards offer a 'Set up multiple monitors' wizard. The graphics cards can be adapted to work with different monitors running at different resolutions.

There is also the option to clone the desktop, with both monitors showing the same image, right down to the Start menu. The button for this is in the display properties, found by right-clicking on the desktop.

USB graphics cards can help if more than one monitor is to be hooked into a laptop but not enough ports are present. This requires a USB 2.0 port, however, since only that standard is fast enough to handle the data flow. External graphics solutions often tax the processor heavily, so this solution is best implemented by laptops with a lot of power under the hood.