A ZIF (Zero Insertion Force) socket is the physical way that Intel's 486 and Pentium microprocessors up to Pentium II connect on the computer motherboard to the data bus. As its name implies, the ZIF socket is designed for ease of manufacture and so that the average computer owner will be able to upgrade the microprocessor. The ZIF socket contains a lever that opens and closes, securing the microprocessor in place.
The ZIF interface evolved through eight variations, each with a differing number of pins and pin layout arrangements. Currently, the best-known is Socket 7, the configuration used in the Pentium microprocessor. (However, the Pentium Pro uses Socket 8.) With the Pentium II microprocessor, which is based on Intel's new P6 micro architecture, Intel has changed to a new connection configuration called Slot 1. In this configuration, the microprocessor comes packaged in a cartridge that fits into a 242-contact or 330-contact slot in the motherboard.
The following table summarizes the Zero Insertion Force (ZIF) socket characteristics for different Intel processors.
|3||237||Inline||486DX,SX,DX2,DX4||3V or 5 V|
|4||273||Inline||60 or 66 MHz Pentium||5 V|
|8||387||Staggered||Pentium Pro||3 V|