A Multiple Monitor Tutorial by PowerPoint MVP Chirag Dalal
Multiple Monitor Support has two components: Hardware and Software.
We'll look at both of these components in detail.
The Hardware Component
Your computer uses video display hardware to convert computer information into something that can be displayed on a monitor or laptop screen. The video display is either on a special video card or is built into the computer itself.
All laptops and some desktops have built-in or on-board video.
To have true multiple monitor support, the video display (which we'll refer to as "video hardware" from now on) must support multiple monitors and must allow independent resolution and color depth settings for each. But as you'll see later, there are other types of multiple monitor support that are less flexible but still useful.
The Software Components
Your software must also be able to support, recognize and use the video hardware's multiple monitor capabilities. There are three levels where this needs to happen:
- Windows itself
- The video hardware's display driver
- PowerPoint and other applications software
Let's take a closer look at each of these levels.
Windows
Microsoft Windows 98, 98SE, ME, Windows 2000, XP and 2003 all have built-in support to recognize multi-monitor configurations. Windows NT4 and earlier and Windows 95 do not.
The Display Driver
A display driver is software that translates graphics commands from generic Windows ones to commands specific to the video hardware.
The display driver recognizes the multi-monitor hardware (the video hardware) and tells Windows about it and the actual number of monitors connected to the system.
Normally, the display driver tells the truth, but there can be a mismatch between the actual number of monitors attached to the machine and the number of them reported by the driver.
PowerPoint and Other Software
Your programs must also recognize multiple monitors and do something useful with them. Windows itself may allow you to spread your display out over several different monitors -- for example, you might be able to put menus and toolbars on one monitor and your working graphics on another. PowerPoint, on a properly configured system, allows you to display your slide show on one monitor and your speakers notes on another ... very handy indeed.
Video hardware and/or display drivers can support multiple modes of operation, including:
- Multi-monitor Clone
- Multi-monitor Span
- True Multi-monitor
Let's look at each of these modes in more detail.
Multi-monitor Clone
Most of the multi-monitor display cards and their drivers have the ability to "clone" the content of one monitor to the other monitors. In the Multi-monitor Clone mode, the operating system is informed that the machine has only one monitor when it actually has several. Behind the scenes, the video hardware or the display driver replicates the content of one monitor to the other monitors.
In clone mode, Windows and applications (including PowerPoint) see only one monitor. They aren't even aware that the output that they produce gets copied over multiple monitors. The same information is shown on both/all monitors.
In the clone mode, one of the monitors is selected as the primary one. It is this monitor that the operating system sees. All other monitors usually have the same display resolution and color depth as the primary monitor.
Clone mode doesn't require the operating system to have multi-monitor support. This mode can be made available on Windows 95 and Windows NT too and even older versions of Windows and DOS.
Clone mode is available on virtually every laptop that has an external monitor connector. You can usually use a special function key combination to alternate among internal video only, external video only and both internal and external video.
Multi-monitor Span
Normal monitors have a 4/3 width-to-height display ratio. Common video resolutions like 640x480, 600x800, 768x1024, 1280x1024, etc. all fall under that ratio. Plasma displays may have 16/9 width-to- height ratios.
Multi-monitor Span mode allows you to set a non-4/3 display resolution as the "desktop" display, then span the entire desktop (usable area) across multiple monitors.
Like Multi-monitor Clone mode, Windows and applications see only one monitor, but now the monitor is "virtual" (not a real physical monitor) and it has an abnormal display resolution.
For instance, if there are two monitors configured as sitting side-by-side, then the display driver would tell Windows that the display resolution has 8/3 ratio - twice the normal width, that is.
And also like Clone mode, Span mode too doesn't require Windows to recognize and support multi-monitor configurations. Span mode can work on Windows 95 and Windows NT.
True Multi-monitor
Clone and Span modes tell Windows that only one monitor is present on the machine. They don't give Windows control over individual monitors, but they don't require Windows to support multiple monitors either.
True Multi-monitor mode is different. Here, the display driver tells Windows the actual number of monitors attached to the computer. Each monitor can have its own display and each can have its own independent display resolution and color depth.
Does your computer have True Multi-monitor support? One way to tell is to right-click the Windows desktop and choose Properties from the popup menu then click the Settings tab of the Display Properties dialog box.
Your computer's Settings tab may look different. The key things to look for are (outlined here in yellow):
- Two or more monitor icons in the dark gray area under "Drag the monitor ..."
- A "Display" dropdown listbox with multiple monitors listed, one for each monitor in the gray area above
- The ability to set the video properties (Screen resolution, Color quality) of each monitor independently
If your laptop doesn't offer true Multi-monitor support, you may be able to add it with a PCMCIA (PC slot) graphics card or a USB external video card. These products tend to come and go, so do some searching on Google or check reviews at New Egg for likely looking products.
You can add Multi-monitor support to a desktop PC by replacing the video display card with a "multi-head" card or, in some cases, by adding an additional card to supplement the one you already have.
PowerPoint recognizes this mode and enables features like Presenter View when it detects that Multi-monitor support is available.
The PowerShow add-in utilizes this mode to extend PowerPoint's multi-monitor support. It enables you to show different slide shows on different monitors simultaneously. It also utilizes this mode to provide span support for individual slide shows. Using PowerShow, you can control what slide show would span how many monitors. True Multi-monitor mode enables PowerShow to let you view the speaker notes on the laptop while viewing the slide show on another display connected to an external device like a video projector.
The SundayStar addin for PowerPoint introduces the following slide show features to PowerPoint running on a computer that supports a multi-monitor configuration:
- Start multiple slide shows on a monitor simultaneously.
- Each slide show has a keyboard shortcut associated with it. Switch between slide shows using the keyboard shortcuts.
- Slide design view stays in-sync with slide show.
- Slide show stays in-sync with slide design view.
SundayStar works with Microsoft PowerPoint 2000, PowerPoint 2002 (XP) and PowerPoint 2003 on Windows 98, Windows Me, Windows 2000 and Windows XP.
Visit the SundayStar webpages for more information.