• graphics accelerators

• accelerator boards

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.

PC Mechanic - online guide to computer hardware 
Contains overviews, purchasing and installation information for PC motherboards, memory, drives, expansion cards, and power supplies. Also contains links to companies and manufacturers and PC hardware related links.

PC Mechanic's expansion cards page
Describes the different types of expansion cards, slots, as well as how to install and configure expansion boards.

Hardware Central
Detailed test reports on the latest desktop and laptop computers. Plus news on trend-setting products just coming into the pipeline.