Video Card and Monitor: Video cards take the output of your computer and send it to a monitor (computer screen) to be viewed.  Modern video cards are typically plugged into the AGP slots in the motherboard.  Older systems typically use PCI or ISA video cards.  The video card output connector extends from the back of the computer case, and the monitor cable is plugged into it.  Some motherboards come with the video included as part of the motherboard, so that you don't need to plug a separate video card into the bus slots.  In this case, the monitor plugs directly into the motherboard (or into a cable that plugs directly into the MB), rather than into an added video board.

PHOTOS:  Desktop case and monitor, ISA PCI and AGP video cards

VIDEOS:  built in video back panel and side, back panel monitor, AGP Video Card install - bare MB, PCI video card install (ATX case), PCI video card install (AT Case), ISA video card install (ATX case), ISA video card install (AT case)

The type of video board you put in a computer determines the number of colors, the number of pixels (dots on the screen), and the quality and speed of the images your computer can create.  More pixels, more colors, and faster draw rates produce better graphics on the monitor screen.  There are a number of different standards which have become obsolete.  The original IBM XT shipped with a monochrome (black and white) card and monitor that could only display text and characters.  That was quickly improved to a "CGA" card that could display 3 colors and 320 pixels (dots) across the screen, and 240 pixels down the screen.  286's typically came with EGA video:  16 colors and better pixel resolution (more dots).  386's and 486's typically came with VGA cards and monitors:  16,256, 64,000, or 24 million colors, and usually 640x480 pixels.  VGA monitors with 256 colors and 640x480 resolution can produce reasonable quality graphics - that's a basic minimum standard to remember.  More colors, pixels, and speed can produce dramatically better video and graphic quality. 

The number of colors and pixels, as well as the speed of display is determined in part by the amount and quality of memory on the video card.  You need at least 512k (1/2 Meg) of memory to produce the essential 256 colors and 640x480 resolution required to run most Windows applications.  More colors and larger displays require more memory.  Modern systems use Super-VGA, XGA, and Super-XGA cards with between 2Megs - 64Megs of very fast memory.  Most can produce at least 800x600 pixels, at a depth of at least 64,000 colors, and are able to display large graphics and animation very quickly.  If you want to build a system for graphic gaming, computer aided drafting, or video editing, you should buy the best video card your budget will allow.  Cards such as the G-Force II, and those with the RIVA TNT2 chipset are very popular at the time of this writing.

Monitors are generally matched to suit video card performance and application.  Computer systems which are meant for gaming, video editing, and other graphic intense applications are typically matched with larger monitors.   Monitors typically come in the following sizes:  14", 15", 17", 19", and 21".  Most common for home systems are 15" and 17".  The screen size is measured diagonally, and the viewable area is typically smaller than the actual screen dimensions.  Most modern monitors will support at least 1024x768 pixels.  Larger monitors typically support more pixels, because on a large monitor icons and images appear grainy, since each individual pixel is so large.  800x600 resolution is the standard for most modern Windows applications.  Monitors also have a "dot pitch" rating - the lower the value, the better the quality of the image.  Also, most modern monitors have a set of controls on the front panel which allows the user to control positioning, height and width stretching, color, shape, and other elements of the computer video, so that it best matches the output of your video card. 

When purchasing a used monitor, make sure your monitor supports the video card and standard you install in the computer.  There are many used VGA, b/w VGA, and even obsolete EGA monitors on the used market which may not even plug into the cable connector of a new video card.

PHOTO:  EGA connector (don’t buy a monitor with this type of cable pin-out, unless you have the very old and obsolete type of video card it plugs into, installed in your machine)

VIDEO:  EGA connector and monitor