LGA 1155

LGA 1155, also called Socket H2, is a zero insertion force flip-chip land grid array (LGA) CPU socket designed by Intel for their CPUs based on the Sandy Bridge (second generation core) and Ivy Bridge (third generation) microarchitectures. Introduced in 2011, it is the successor of LGA 1156 (known as Socket H) and marked the beginning of UEFI secure boot with support on some versions of later boards and was itself succeeded by LGA 1150 in 2013. Along with selected variations of LGA 2011 socket, Socket G2, BGA 1023, BGA 1224, and BGA 1284 as well as LGA 1356, it is the last Intel socket to fully support Windows XP, Windows Server 2003, Windows Vista, and Windows Server 2008. The last processors supporting this socket ceased production in mid-2015. LGA 1155 has 1155 protruding pins to make contact with the pads on the processor. The pins are arranged in a 40×40 array with a 24×16 central void and additional 61 omitted pins (two adjoining the central void, six in each of the four corners, and 35 in groups around the perimeter), yielding the 1600 − 384 − 61 = 1155 pin count. Processors for LGA 1155 and LGA 1156 sockets are not compatible with each other since they have different socket notches.