What Is Socket 1?

Socket 1 typically refers to the socket introduced by Intel® for use with x86 processors, such as the 486 central processing unit (CPU). At one time it was referred to as the “OverDrive socket” due to its use with initial OverDrive CPUs, but since not all OverDrive CPUs worked with this socket, this name is seldom used. This should not be confused with “slot 1” CPU connectors that refer to a connection used with single-edged contact cartridge (SECC) style CPUs. Socket 1 became obsolete, however, as development of newer CPU sockets continued, including socket 2 and later sockets that were eventually replaced by slot 1.

The term “socket 1” refers to a particular type of socket that was designed by Intel® for use with different types of CPUs within the x86 family of processors. A CPU is a type of processor used in a computer that typically provides the overall processing power for that computer. The CPU is connected inside of a computer to the motherboard within that computer, and the way in which it is connected is through a “socket” or “slot.” These sockets often have different names, usually set by the manufacturer, which can indicate the way in which the socket is designed or different iterations of sockets for a particular market.

Socket 1 was a CPU socket that consisted of 169 connections for the pins on a CPU. These connections were arranged in a 17 x 17 connection grid, with an 11 x11 section missing from the middle, leaving three full rows of pins on each side. An extra pin connection was made at a corner of the middle section, to ensure a CPU was inserted properly into the socket 1 connections, for a total of 169 connections. This made the socket fairly backward compatible with some older CPUs that had 168 connections.

While socket 1 was first introduced for use with OverDrive CPUs, it typically only worked with the first generation of OverDrive chips. Later processors were often designed for sockets with four rows, rather than the three rows found on socket 1, such as socket 2. This was followed by socket 3, then socket 4, and on up until the introduction of socket 8. Socket 8 was largely replaced by the slot 1 connection type for Intel® Pentium® CPUs, which is similar in appearance to a slot used for random access memory (RAM).