Peripheral Component Interconnect
From Unofficial BOINC Wiki
This is a mechanism that allows connection of expansion cards into a computer system. The standard was first proposed as a means of increasing the speed and reliability of the connections of the cards to the rest of the computer system. The PCI standard was later expanded by widening the number of bits transferred (from 32 to 64 bits) with the initial speed of 33 MHz raised to 66 MHz. This is the primary interconnect mechanism used in most of the Personal Computers made today. The only other interconnect that is of interest is Accelerated Graphics Port (AGP) which is only used for connecting a graphics card to the computer system.