The PC primer: Hardware: Video

Video

Video has come a long way since the early Hercules graphics cards, which gave astounding quality (for their time, 1982) in first IBM PC's.

The Hercules graphic card was both a graphic standard and the name of the manufacturer was founded by a Thai who wanted to write his Doctoral thesis in his native language and the card produced allowed lots of 'scripts' such as Arabic, or Japanese to be rendered, although on a screen which could display 80×25 text characters

This is what the output from a Hercules card looks like 80 x 25 characters.

Graphics cards

CRT monitors (Cathode Ray Tube)

Basically the same as a standard TV, the crt monitor is now on the way out and will soon be difficult to get hold of. Apart from their bulk, they use far more electricity the LCD monitor, a 17" CRT using about 150w.

LCD monitors

The image quality is still not quite up to the standard of the CRT, but it's getting there.
The power consumption is generally about 100w for a 17" model, however if it has inbuilt speakers this will increase.

Data Projectors

Very much the 'In' thing, with LCD projectors appearing in boardrooms and classrooms all over the planet. They vary from little things the budding executive can carry around with their laptop, to HDV (High Definition Video) cinema projectors.

Using more than one monitor

There may be occasions when you need to display the output from a PC on more than one monitor, easy with a Laptop, as most laptops have a secondary video output, often used to work LDC projectors. More difficult for the desktop PC.
If you need to do this on a regular/permanent basis then you might invest in a 'Dual head' Video card, two outputs both capable of displaying an image, or indeed two different images.

One of the best reasons to use two displays is to 'split' the desktop. This is a popular way of working in publishing, where you have your 'working' desktop on one monitor and the page layout on another. Bear in mind that you can 'Drag and drop' items between desktops.

The image below shows such a desktop. The properties box is showing and while monitor 1# is set to 1027 x 768 resolution, monitor 2# is at 800 x 600.

Video splitters

Using more than one monitor to show the same image can be achieved with the introduction of a 'Video splitter' like the one shown. An external, powered amplifier with, in this case one in and two video signals out, splitters with more outputs are available. As I've said you get the same image through both outputs and these devices tend to be used in fixed locations such as teaching, or board rooms where PC based presentations happen.