Socket 775 (LGA775 / Socket T)

Socket 775, also called Socket T or LGA775, is a Land Grid Array (LGA) socket used for the most recent generations of desktop Intel microprocessors starting from Pentium 4 and up to Core 2 Quad / Core 2 Extreme families. The socket LGA775 supports Intel CPUs from 1.8 to 3.8 GHz with Front-Side Bus frequencies ranging from 533 MHz to 1600 MHz. This socket superseded socket 478.

The Socket 775 differs from all earlier x86 sockets in the sense that it doesn't have pin holes. Instead, the socket has 775 gold-plated contacts arranged as a grid 33 x 30 contacts with 15 x 14 section de-populated in the center, with one corner contact and 4 contacts on two sides on the socket removed. After the processor is placed into the socket it has to be secured by pushing down socket's load lever. The LGA775 socket is guaranteed to last at least 20 insert cycles.

The size of the socket LGA775 is 1.48" x 1.48" (3.75 cm x 3.75 cm), or about 15% larger than the size of socket 478. At the same time the socket 775 has 60% more contacts. The increase in the number of contacts without equivalent increase of socket size was achieved by reducing the distance between contacts. Another advantage of the new socket design is the lower resistance of the contacts, which reduces the amount of heat generated by socket and socket contacts.

LF-LGA775 socket is RoHS-compliant version of LGA775 socket.

  Supported processors  

All processors in the table below will physically fit into the socket LGA775, but not all of them are supported by all motherboards. If you're upgrading an old computer system please make sure that the CPU is compatible with your motherboard. Please see "Upgrading socket 775 motherboards" section below for information on how to determine what microprocessors can be supported by your motherboard.

CPU Family	Frequency	The fastest CPU(s)
Celeron 400 series	1.6 GHz - 2 GHz	Celeron 440
Celeron D	2.4 GHz - 3.6 GHz	Celeron D 365
Celeron Dual-Core	1.6 GHz	Celeron E1200
Core 2 Duo	1.8 GHz - 3.16 GHz	Core 2 Duo E8500
Core 2 Extreme	2.66 - 3.2 GHz	Core 2 Extreme QX9770
Core 2 Quad	2.4 GHz - 2.83 GHz	Core 2 Quad Q9550
Pentium 4	2.66 GHz - 3.8 GHz	Pentium 4 672 Pentium 4 670 Pentium 5 571 Pentium 5 570J
Pentium 4 Extreme Edition	3.2 GHz - 3.73 GHz	JM80547PH1092MM (BX80547PH3730F)
Pentium D	2.66 GHz - 3.6 GHz	Pentium D 960
Pentium Dual-Core desktop	1.6 GHz - 2.2 GHz	Pentium Dual-core E2220
Pentium Extreme Edition	3.2 GHz - 3.73 GHz	Pentium Extreme Edition 965
Xeon 3000 series	1.86 GHz - 3 GHz	Xeon E3110 Xeon 3085 Xeon X3230

There are no CPUs from other manufacturers compatible with socket LGA775.

  Compatible package types  

775-land Flip Chip Land Grid Array package.

The picture on the right shows the bottom view of the 775-land LGA package.

  Upgrading socket 775 motherboards  

To determine the fastest supported processor for socket 775 motherboard you'll need to:

• Determine manufacturer and model of the motherboard,
• Search on manufacturer's website for the motherboard model.

  Processor Installation  

For processor installation instructions please look at your motherboard manual, or go to this page on Intel website.