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Expansion Board

Webopedia Staff
Last Updated May 24, 2021 7:42 am

An expansion board is a printed circuit board that you can insert into a computer to give it added capabilities. For example, all of the following are expansion boards:

  • video adapters
  • graphics accelerators
  • sound cards
  • accelerator boards
  • internal modems
  • Expansion boards for PCs can be half-size (also half-length) or full-size (also full-length). Most PCs have slots for each type of board. A half-size board is sometimes called an 8-bit board because it can transmit only 8 bits at a time. A full-size board is called a 16-bit board. In addition, some expansion boards are designed to operate with a local bus, such as PCI.

    Expansion boards are also called adapters, cards, add-ins, and add-ons.