LGA 771, also known as ''Socket J'', is a CPU interface introduced by Intel in 2006. It is used in Intel

Core microarchitecture The Intel Core microarchitecture (provisionally referred to as Next Generation Micro-architecture, and developed as Merom) is a multi-core processor microarchitecture launched by Intel in mid-2006. It is a major evolution over the Yonah, the p ...

and NetBurst microarchitecture(Dempsey) based DP-capable server processors, the Dual-Core

Xeon Xeon ( ) is a brand of x86 microprocessors designed, manufactured, and marketed by Intel, targeted at the non-consumer workstation, server, and embedded system markets. It was introduced in June 1998. Xeon processors are based on the same a ...

is codenamed

Dempsey Dempsey is a surname of Irish origin. Background Dempsey is an anglicised form of Ó Díomasaigh, 'descendant of Díomasach'; this personal name is the Irish adjective ''díomasach'' 'proud'. The family originated in the Kingdom of Uí Failghe ...

, Woodcrest, and Wolfdale and the Quad-Core processors Clovertown, Harpertown, and Yorkfield-CL. It is also used for the Core 2 Extreme QX9775, and blade servers designated under Conroe-CL. It was succeeded by

LGA 1366 LGA 1366 (land grid array 1366), also known as Socket B, is an Intel CPU socket. This socket supersedes Intel's LGA 775 (Socket T) in the high-end and performance desktop segments. It also replaces the server-oriented LGA 771 (Socket J) in the e ...

for the Nehalem-based Xeon processors.

Technical specifications

As its name implies, it is a

land grid array The land grid array (LGA) is a type of surface-mount packaging for integrated circuits (ICs) that is notable for having the pins on the socket (when a socket is used) rather than the integrated circuit. An LGA can be electrically connected to a ...

with 771 contacts. The word "socket" in this instance is a misnomer, as the processor interface has no pin holes. Instead, it has 771 protruding lands which touch contact points on the underside of the

microprocessor A microprocessor is a computer processor where the data processing logic and control is included on a single integrated circuit, or a small number of integrated circuits. The microprocessor contains the arithmetic, logic, and control circu ...

. The "J" in "Socket J" refers to the now-canceled processor codenamed " Jayhawk", which was expected to debut alongside this interface. It is intended as a successor to

Socket 604 Socket 604 is a 604-pin microprocessor socket designed to interface an Intel's Xeon processor to the rest of the computer. It provides both an electrical interface as well as physical support. This socket is designed to support a heatsink. Launch ...

and takes much of its design from

LGA 775 LGA 775 (land grid array 775), also known as Socket T, is an Intel desktop CPU socket. Unlike PGA CPU sockets, such as its predecessor Socket 478, LGA 775 has no socket holes; instead, it has 775 protruding pins which touch contact points on the ...

and is almost pin compatible with LGA 775. Socket 771 CPUs are rotated 90 degrees and have two pins swapped. Small adapters developed by Chinese computer DIY enthusiasts are available to allow LGA 771 CPUs to be installed in LGA 775 motherboards, if the BIOS microcode supports them (but it is also possible to add supporting microcode manually). This also allows for overclocking of Xeon (socket 771) processors when used in the correct (socket 775) motherboards. Some overclockers have managed quite substantial overclocks such as 4.023GHz on a Xeon X5492 for a total overclock of just over 18%. Using a xeon can be a quite viable upgrade path for old LGA775 systems if you have the correct motherboard, chipset and bios revision.

Single core processors

Dual core processors

** Hyperthreading supported only on 50xx series processors(codenamed Dempsey) Xeon E5140 Processor 2022-11-29

Quad core processors

References

{{Intelsock Intel CPU sockets

Technical specifications

Single core processors

Dual core processors

Quad core processors

See also

References