Slot 1 and Slot 2 are names for the way Intel P6-based microprocessor s connect to a computer motherboard so that it makes contact with the built-in paths called the data bus . Slot 1 and Slot 2 were developed by Intel as a replacement for its Zero Insertion Force ( ZIF ) sockets, the most familiar of which is Socket 7 for Intel's Pentium processors. For the Pentium II, which is based on Intel's P6 micro architecture, Intel switched to the Slot 1 configuration. With the slot approach, the microprocessor is packaged in a cartridge, known as a Single Edge Cartridge, that is easily inserted into a slot designed into the motherboard. The new approach will make connection to the faster and larger number of data paths in future processors more feasible.
Officially, Intel now refers to Slot 1 as the 242-contact slot connector and Slot 2 as the 330-contact slot connector. Besides the Pentium II, Intel's Celeron processor also uses the Slot 1 configuration. Intel's high-end Pentium II Xeon processor uses the Slot 2 configuration. Intel is said to be developing a Slot M.
Since the motherboards are different, computer owners with Socket 7 Pentiums will not be able to upgrade to the newer P6 Pentiums with Slot 1 and Slot 2 configurations. and Cyrix , which offer processors that compete with the Pentium II, say they plan to continue using the Socket 7 motherboard.