A PC dual screen system is really just your regular PC with a video card capable of running two monitors in tandem. Having two monitors can be quite helpful. It means you'll have more desktop and viewing space. You won't need to keep switching among several open windows. With two screens, you can at least keep a window open and static in one and then use the other screen for switching. A dual screen system can also be an advantage when you're multitasking or constantly correlating data between two applications.
- Dual screen video card. The essential hardware in a PC dual screen system is naturally the dual screen video card. Unlike a regular video card which has only one port -- one connection for a monitor cable to plug in, a dual screen video card would have two of these ports. It's still actually possible to set up a dual screen system by installing two video cards, one for each monitor. But that method isn't recommended as IRQ (Interrupt Request) conflicts are very likely to occur. Each video card would be fighting for the central processor's attention. Some system resources tweaking could remedy this. But do you really want to muck about with your computer's CMOS settings? Stick with a dual screen video card. It's safer, easier to install, and might not even cost as much as two video cards.
- Motherboard support. If you're going to be building your PC dual screen system from the ground up, then you don't have to worry too much about your motherboard supporting a dual screen video card. Since you'll be purchasing the components individually, you can easily match motherboard to video card. If you're upgrading an existing PC to dual screen, then you'll have to think about support and compatibility. One main consideration here is the motherboard's socket for video cards. Older boards have AGP (Accelerated Graphics Port). The new standard is PCI-E (Peripheral Component Interconnect Express). These two are mutually exclusive, meaning an AGP type of video card won't physically fit into a PCI-E socket and vice versa.
- DVI and VGA. Dual screen video cards as mentioned earlier have two ports for plugging in two separate monitors. But they're not the same kind of ports. One port is VGA (Video Graphics Array) which is the old standard for monitor connections and the other port is DVI (Digital Visual Interface), a new video interface that can, as the name implies, carry digital signals. If you haven't purchased your second monitor then consider looking for one that uses DVI, as your old monitor is likely based on VGA. If you already have two monitors that happen to be both VGA or both DVI, then you can remedy the situation by using the appropriate adapters, either VGA-to-DVI or DVI-to-VGA.
Once physically plugged in to your motherboard, you will need to install the dual screen video card's accompanying software. These are essentially the drivers that will run the video card and activate its dual screen capabilities. To avoid any conflicts make sure you've uninstalled the old video card's drivers or control software from your system before putting in the new one.