939pin

939pin, or Socket 939, is an AMD desktop CPU socket used primarily with the Athlon 64 family. It is a 939-pin Pin Grid Array (PGA) socket, meaning the processor carries 939 pins that insert into the motherboard’s socket. The design was part of AMD’s K8 platform and facilitated dual-channel memory by integrating the memory controller on the CPU.

Introduced in the mid-2000s, Socket 939 supported several generations of Athlon 64 processors, including single-core and dual-core variants such as the Athlon 64 and Athlon 64 X2, as well as certain Sempron 64 models. Motherboards for 939 sockets commonly provided PCI Express graphics slots, multiple PCIe lanes, and support for various chipsets from major vendors. Memory support was typically dual-channel DDR SDRAM, with common module speeds around DDR400 (PC3200), though actual memory performance depended on the CPU and motherboard capabilities.

Socket 939 was eventually succeeded by Socket AM2, which introduced DDR2 memory support and a different pin configuration (940 pins). Because of the different pinouts and memory types, 939 CPUs are not compatible with AM2 (or later) boards, and vice versa. The 939 ecosystem matured during the mid-to-late 2000s and gradually phased out as AMD shifted toward newer sockets and memory technologies.

See also: Socket 754, Socket AM2, Athlon 64, AMD64, DDR SDRAM, PCI Express.