What Is Socket 370?

Socket 370 is a type of central processing unit (CPU) socket that semiconductor manufacturer Intel Corporation used for its Pentium III and Celeron CPUs, or personal computer (PC) microprocessors. The number "370" stands for the total amount of holes that the socket possesses to accommodate the processor pins. Socket 370 is also referred to as the PGA370, with "PGA" being an acronym for "pin grid array." This is a form of integrated circuit packaging that consists of a square-shaped structure with neatly aligned rows of pins. Like other CPU sockets, the Socket 370 provides the support and connection of the microprocessor when placed on the motherboard, making it easy to remove or swap them without causing damage to any of the components involved.

Initially, the Socket 370 was made for the single-core Intel Celeron chips, which debuted in 1998 as Intel's low-end processors. Specifically, it was compatible with the Mendocino-codenamed Celeron CPUs, which Intel designed for application on laptop PCs. The socket design used for these chips, called Mobile Celeron, or mobile processors, due to their manner of use, was PPGA, or "plastic pin grid array." The chips themselves have a data transfer rate of 66 megahertz (MHz), a processing speed range of 266 to 466 MHz, and a core voltage range of 1.5 to 1.9 volts (V).

With the advent of the Pentium III, Intel's third iteration of its then-premier brand, the company decided to revise the Socket 370 according to its specifications. It accomplished this by tinkering with its electrical components, thus rendering Celeron Mendocino chips incompatible with this version. The Pentium III CPUs in particular that received the Socket 370 are codenamed Coppermine. These computer chips have a processing speed range of 500 to 1,133 MHz, data transfer rates of 100 MHz and 133 MHz, and a 1.6V to 1.75V core voltage range.

Intel made the third and last major revision with the April 2001 debut of the Tualatin-codenamed Pentium III CPUs, which are notably smaller than the Pentium III Coppermine processors. Again, the company altered the electrical components. This consequently led to the Socket 370 accommodating Tualatin processor speed range, data transfer rates and core voltages of 1 to 1.4 gigahertz, 100 MHz and 133 MHz, and 1.45V and 1.5V, respectively.

The second and third versions of the Socket 370 are of the flip-chip pin grid array, named FC-PGA and FC-PGA2, respectively. Users can get a PPGA-to-FC-PGA adapter to use the original socket for the Coppermine CPUs. Similarly, Tualatin Pentium III chips need an adapter to work on sockets with the first FC-PGA design. In addition to its targeted accommodation for Tualatin chips, the FC-PGA2 is actually compatible with Celeron chips.