LGA 1155

LGA 1155

Type	LGA
Contacts	1155
Processor dimensions	37.5 × 37.5 mm^[1]
Processors	Sandy Bridge, Ivy Bridge
Predecessor	LGA 1156
Successor	LGA 1150
This article is part of the CPU socket series

View of the socket LGA 1155 on an Intel Core i7 Sandy Bridge 2600K model CPU

LGA 1155, also called Socket H2, is a socket used for Intel microprocessors based on Sandy Bridge and Ivy Bridge microarchitectures. Its incompatible counterpart for Intel's high-performance desktops and servers is LGA 2011.

LGA 1155 is designed as a replacement for LGA 1156 (known as Socket H). 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. However, cooling systems are compatible between LGA 1155 and LGA 1156 sockets, as the processors have the same dimensions, profile and construction, and similar levels of heat production.^[2]

Integrated USB 3.0 support is present in the Z75, Z77, H77, Q75, Q77 and B75 chipsets intended for Ivy Bridge CPUs. Refer to list of Intel chipsets for the complete list of LGA 1155 chipsets.

Original Sandy Bridge chipsets

Sandy Bridge chipsets, except Q65, Q67 and B65, support both Sandy Bridge and Ivy Bridge CPUs through a BIOS upgrade.^[3] Sandy Bridge based processors officially support up to DDR3-1333 memory, however in practice speeds up to DDR3-2133 have been tested to work successfully.^[4]

The H61 chipset only supports one double-sided DIMM per memory-channel and therefore is limited to 16 GB instead of the 32 GB like the others support.^[5] On motherboards with four DIMM slots, only four single-sided DIMMs can be installed.^[6]

Name	B65	H61	Q67	H67^[7]	P67	Z68^[8]
Overclocking	GPU				CPU + RAM	CPU + GPU + RAM
Allows using built-in GPU with Intel Clear Video Technology	Yes				No	Yes
Maximum USB 2.0 ports¹	12	10	14
Maximum SATA 2.0/3.0 ports	4 / 1	4 / 0	4 / 2
Main PCIe Configuration	1 × PCIe 2.0 ×16				1 × PCIe 2.0 ×16 or 2 × PCIe 2.0 ×8
Secondary PCIe	8 × PCIe 2.0	6 × PCIe 2.0	8 x PCIe 2.0
Conventional PCI support²	Yes	No	Yes	No
Intel Rapid Storage Technology (RAID)	No		Yes
Smart Response Technology	No					Yes
Ivy Bridge Processor Support	No	Yes	No	Yes
Intel Active Management, Trusted Execution, Anti-Theft, and vPro Technology	No		Yes	No
Release Date	February 2011		May 2011	January 2011		May 2011
Max TDP	6.1 W
Chipset lithography	65 nm

^[9] Table updated with the latest information from Intel ARK

¹ USB 3.0 is not supported by any of these chipsets. Motherboard manufacturers may use external hardware to add USB 3.0 support.

² Although some of the chipsets do not support conventional PCI, motherboard manufacturers may include support through the addition of third party chips.

Ivy Bridge chipsets

All Ivy Bridge chipsets and motherboards support both Sandy Bridge and Ivy Bridge CPUs. Ivy Bridge based processors will officially support up to DDR3-1600, up from DDR3-1333 of Sandy Bridge. Some consumer Ivy Bridge chipsets will also allow overclocking of K-series processors.^[10]

Name	B75	Q75	Q77	H77	Z75	Z77
Overclocking	CPU(Bclk) + GPU				CPU + GPU + RAM
Allows using built-in GPU	Yes
Intel Clear Video Technology	Yes
RAID	No	Yes
Maximum USB 2.0/3.0 ports	8 / 4	10 / 4
Maximum SATA 2.0/3.0 ports	5 / 1		4 / 2
Main PCIe Configuration³	1 × PCIe 3.0 ×16				1 × PCIe 3.0 ×16 or 2 × PCIe 3.0 ×8	1 × PCIe 3.0 ×16 or 2 × PCIe 3.0 ×8 or 1 × PCIe 3.0 ×8 + 2 × PCIe 3.0 ×4
Secondary PCIe	8 × PCIe 2.0
Conventional PCI⁴	Yes			No [11]
Intel Rapid Storage Technology	No		Yes
Intel Anti-Theft Technology	Yes
Smart Response Technology	No		Yes		No	Yes
Intel vPro	No		Yes	No
Release Date	April 2012^[12]
Max TDP	6.7 W
Chipset lithography	65 nm^[13]

^[14]

³ For PCIe 3.0 capability, the Ivy Bridge CPU must have the relevant PCIe 3.0 controller built in. Some Ivy Bridge CPUs only have a PCIe 2.0 controller built in.

⁴ Although some of the chipsets do not support conventional PCI, motherboard manufacturers may include support through the addition of third party chips.