LGA 1156

LGA 1156

Type	LGA
Chip form factors	Flip-chip land grid array
Contacts	1156
FSB protocol	PCIe 16× (video) + 4× (DMI) + 2 DP (FDI), 2 DDR3 channels
Processor dimensions	37.5 × 37.5 mm
Processors	Intel Celeron Intel Core i3 Intel Core i5 Intel Core i7 Intel Pentium Intel Xeon
This article is part of the CPU socket series

LGA 1156, also known as Socket H or H1, is an Intel desktop CPU socket. LGA stands for land grid array. Its incompatible successor is LGA 1155.

LGA 1156, along with LGA 1366, were designed to replace LGA 775. LGA 1156 is very different from LGA 775. LGA 775 processors were connected to a northbridge using the Front Side Bus. With LGA 1156, the features that were traditionally on a northbridge are integrated onto the processor. The LGA 1156 socket allows the following connections to be made from the processor to the rest of the system:

• PCI-Express 2.0 ×16 for communication with a graphics card. Some processors allow this connection to be divided into two ×8 lanes to connect two graphics cards. Some motherboard manufacturers use Nvidia's NF200 chip to allow even more graphics cards to be used.
• DMI for communication with the Platform Controller Hub (PCH). This consists of a PCI-Express 2.0 ×4 connection.
• FDI for communication with the PCH. This consists of two DisplayPort connections.
• Two memory channels for communication with DDR3 SDRAM. The clock speed of the memory that is supported will depend on the processor.

LGA 1156 socket and processors will be discontinued sometime in 2012, along with LGA 1366.

Supported processors

Code name	Brand name	Model (list)	Frequency	Cores/Threads	Max Memory Speed
Lynnfield	Core i5	i5-7xx	2.66-2.8 GHz	4/4	DDR3-1333
	Core i7	i7-8xx	2.8-2.93 GHz	4/8
	Xeon	L34xx	1.86 GHz	4/4 or 4/8
		X34xx	2.4-2.93 GHz
Clarkdale	Celeron	G1xxx	2.26 GHz	2/2	DDR3-1066
	Pentium	G6xxx	2.80 GHz	2/2
	Core i3	i3-5xx	2.93-3.2 GHz	2/4	DDR3-1333
	Core i5	i5-6xx	3.2-3.6 GHz	2/4

All LGA 1156 processors and motherboards made to date are interoperable, making it possible to switch between a Celeron, Pentium, Core i3 or Core i5 with integrated graphics and a Core i5 or Core i7 without graphics. However, using a chip with integrated graphics on a P55 motherboard will (in addition to likely requiring a BIOS update) not allow use of the on-board graphics processor, and likewise, using a chip without integrated graphics on a H55, H57 or Q57 motherboard will not allow use of the motherboard's graphics ports.

Supported chipsets

The Desktop chipsets that support LGA 1156 are Intel's H55, H57, P55, and Q57. Server chipsets supporting the socket are Intel's 3400, 3420 and 3450

See also

• List of Intel microprocessors
• List of Intel Core i3 microprocessors
• List of Intel Core i5 microprocessors
• List of Intel Core i7 microprocessors
• List of Intel Pentium microprocessors
• List of Intel Celeron microprocessors
• List of Intel Xeon microprocessors
• List of future Intel microprocessors
• Clarkdale (microprocessor)
• Lynnfield (microprocessor)
• LGA 775
• LGA 1366