In order to expand the capabilities of the motherboard, you need to install add-on cards on the expansion slots provided on the motherboard. These PC expansion cards are available in various types to match the different adapter slots in PC. The different types of slots, already explained in lesson on motherboard components. The expansion slots can be either ISA, PCI, PCI-express or AGP types.
Different types of PC expansion cards
• Video/Graphics Cards
• TV out Cards
• Network/Lan Cards
• Communication Cards
• Internal modem
• Sound Cards
Graphics Card Types.
Since video cards are the most used expansion cards in PC top date, I will be discussing only these cards. In older series of motherboards, you need to get an additional graphics card in order to get the display output but today, there is an integrated display chip. You need to buy additional display card in order to match the graphics requirement of latest application or games that require high-end graphics.
The Video adapters have either a 9pin D-Type Female connector or 15 pin D type Female connector.
Hierarchy of video cards
• MDA => Monochrome Display Adaptor
• CGP => Color Graphic adaptor with printer port
• MCGP => MultiSync Colour Graphic adaptor with printer port
• EGP => Enhanced Graphics adaptor with printer Port
• VGA => Video Graphics Array
• SVGA => Super Video Graphics Array
• AGP => Accelerated Graphics Port
|Card Type||Connector Type||Video RAM||Bus|
|MDA||RCA similar to audio in pin||8 Kb||8 bit|
|CGP||9 pin D type Female||16 Kb||8 bit|
|MCGP||9 pin D type Female||64 Kb||8 bit|
|EGP||9 pin D type Female||256 Kb||8 bit|
|VGA||15 pin D type Female||Max 512 Kb||16 bit|
|SVGA||15 pin D type Female||1 Mb & Above||16 bit|
|AGP||15 pin D type Female||128mb & above||64 bit|
These PC expansion cards are also termed as I/O (input/output) cards or add-on cards. This card can be easily installed in their respective slots with just a simple push. The electrical connectivity is automatically created after inserting the card since both the expansion cards and the slots have electrically conductive pins and these cards are powered by the motherboard slots.