LGA 1155

LGA 1155
Artem S. Tashkinov · CC BY-SA 3.0 · source
Name	LGA 1155
Created	2011
Manufacturer	Intel Corporation
Form factor	Land Grid Array (LGA)
Contacts	1155
Predecessor	LGA 1156
Successor	LGA 1150

LGA 1155 LGA 1155 is a CPU socket introduced by Intel Corporation for desktop processors based on the Sandy Bridge and Ivy Bridge microarchitectures. It served as a mainstream platform for processors used in systems by vendors such as Dell, HP Inc., Lenovo, and ASUS and was supported by motherboard manufacturers including ASRock, Gigabyte Technology, and MSI. The socket played a central role during the transition from the second to the third generation of Intel Core processors and intersected with product lines from Intel Xeon and integrated graphics families like Intel HD Graphics.

Overview

LGA 1155, also known by Intel platform code names tied to the corresponding microarchitectures, was released to provide electrical and mechanical compatibility for CPUs that integrated memory controllers, PCI Express lanes, and integrated graphics. The platform was central to desktop ecosystems dominated by Microsoft Windows 7, Ubuntu, and Red Hat Enterprise Linux deployments in enterprise and consumer markets. OEM adoption occurred alongside partnerships with chipset vendors such as Intel Corporation itself and third-party peripheral ecosystem companies like NVIDIA Corporation and AMD for discrete graphics complementarity. Industry events such as CES and Computex Taipei featured motherboards and systems built on this socket.

Technical specifications

The socket uses a Land Grid Array with 1,155 protruding lands that interface with matching pads on the processor package; it allows for a zero insertion force mechanism via a retention bracket and load plate standardized in Intel desktop platforms. Electrical characteristics reflect support for dual-channel DDR3 SDRAM memory controllers and PCI Express configurations routed through platform controller hubs designed by Intel Corporation. Thermal management considerations reference Thermal Design Power envelopes specified per model by Intel Corporation and influenced cooling solutions from firms like Cooler Master, Noctua, and Corsair. The mechanical outline aligns with Intel's reference mechanical drawings used by motherboard manufacturers such as Foxconn and Pegatron.

Compatibility and supported processors

LGA 1155 supports a range of Intel Core processors from the second-generation Intel Core i7 (Sandy Bridge), Intel Core i5 (Sandy Bridge), and Intel Core i3 (Sandy Bridge) families to the third-generation Intel Core i7 (Ivy Bridge), Intel Core i5 (Ivy Bridge), and Intel Core i3 (Ivy Bridge) families, plus select Intel Pentium (Sandy Bridge), Intel Celeron (Sandy Bridge), and Intel Xeon E3 variants. Compatibility is constrained by microcode and chipset features; motherboard vendors such as ASUS and Gigabyte Technology released BIOS updates to enable select processor support, while some combinations required specific firmware-level updates coordinated with vendors like Intel Corporation and retail channels including Newegg and Amazon (company). Notebook-class product lines from Acer and Toshiba did not typically use this desktop socket, reflecting OEM segmentation strategies.

Chipsets and motherboard features

Platform controller hubs (chipsets) paired with LGA 1155 included Intel families such as the Intel H61, Intel H67, Intel P67, Intel Z68, Intel Z77, and Intel B75 series, each exposing differing features like integrated graphics routing, overclocking capabilities, and storage interfaces. High-end chipset models supported SATA configurations, multiple PCI Express lanes for multi-GPU setups compatible with NVIDIA SLI and AMD CrossFireX, and Intel technologies such as Intel Rapid Storage Technology and Intel Smart Response Technology. Motherboard form factors adhering to standards from the Distributed Management Task Force and manufacturers included ATX, Micro-ATX, and Mini-ITX layouts with I/O from vendors like Realtek and Intel Ethernet controllers, and expansion cards from companies such as EVGA and ASRock.

Market history and adoption

Introduced amid competition with AMD product cycles including the AMD FX series, LGA 1155 coincided with mainstream adoption driven by enterprise refresh programs from firms like IBM partners and educational procurement through distributors such as CDW. Retail uptake benefited from bundled platforms in systems sold by HP Inc. and Dell, and DIY enthusiasts supported platform longevity via aftermarket cooling and overclocking communities centered on forums like Tom's Hardware and AnandTech. Key product announcements at Intel Developer Forum and trade shows raised visibility, while supply chain events involving manufacturers such as Foxconn influenced motherboard availability. Market analysis firms like Gartner and IDC tracked desktop PC shipments affected by the socket's lifecycle.

Successors and legacy

LGA 1155 was succeeded by LGA 1150, which supported later Intel microarchitectures and introduced new platform features; successor transitions involved motherboard replacement due to pinout and chipset changes, a pattern echoed in previous Intel socket changes such as from LGA 1156. The platform's legacy includes its role in popularizing integrated CPU graphics performance improvements credited to Intel HD Graphics evolution and enabling mainstream overclocking cultures. Enthusiast and enterprise hardware remains in operation in legacy deployments within organizations like US Department of Defense contracting ecosystems and enthusiast retro builds featured on community sites such as Reddit (website) and Linus Tech Tips. The socket is documented in hardware archives maintained by preservation projects and hardware museums hosted by institutions like the Computer History Museum.

Category:Intel CPU sockets