Socket S1 is the CPU socket type used by AMD for their Turion 64, Athlon 64 Mobile, Phenom II Mobile and later Sempron processors, which debuted with the dual-core Turion 64 X2 CPUs on May 17, 2006.

Technical specifications

Socket S1 is a 638 pin, low profile, ZIF, 1.27mm pitch socket. It replaces the existing Socket 754 in the mobile computing segment (e.g. laptops) as well as the microPGA Socket 563 form factor. Socket S1 CPUs can include support for dual-channel DDR2 SDRAM, dual-core mobile CPUs, and virtualization technology, and compete with the mobile Intel Core 2 processor series.

Socket S1 revisions

Different generations of processors used various pinouts of the S1 socket; processors were not necessarily electrically-compatible with each socket even if they fit mechanically.