LGA 775

LGA 775. Also known as Socket T, it is a land grid array (LGA) CPU socket used by Intel Corporation for desktop central processing units spanning several generations. Introduced in 2004, it succeeded the pin grid array Socket 478 and was a foundational platform for the transition from NetBurst to the Core microarchitecture. Its long lifespan and broad processor support made it one of the most significant and widely used sockets in personal computer history.

Overview

LGA 775 was formally launched in June 2004 alongside the Prescott-core Intel Pentium 4 processors and the Intel 925X chipset. This socket represented a major physical departure for Intel, moving the fragile pins from the CPU to the motherboard socket itself. The platform was central to Intel's competitive response against Advanced Micro Devices during the mid-2000s, particularly with the successful introduction of the Intel Core 2 family. Its longevity was supported by numerous chipset revisions from Intel and key partners like ATI Technologies and NVIDIA, allowing it to remain relevant for over five years in a rapidly evolving market.

Technical specifications

The socket features 775 lands and uses a flip-chip land grid array interface, requiring a clamping mechanism and a metal load plate to secure the processor. It supported front-side bus (FSB) speeds of 800 MT/s, 1066 MT/s, and later 1333 MT/s. Unlike its predecessor, LGA 775 motherboards required specific voltage regulator module (VRM) designs to deliver power to different CPU families. The socket was compatible with DDR2 SDRAM and, with later chipsets, DDR3 SDRAM, and it facilitated interfaces like PCI Express for graphics from companies such as AMD (then ATI) and NVIDIA. Thermal design power (TDP) support varied widely across its lifespan, accommodating processors from energy-efficient models to high-TDP Intel Pentium Extreme Edition chips.

Supported processors

LGA 775 supported an exceptionally wide range of Intel processors. Initial models included the Prescott and Cedar Mill Intel Pentium 4 CPUs, as well as Smithfield and Presler Intel Pentium D dual-core chips. Its most notable and performance-defining support was for the entire Intel Core 2 line, including the Conroe, Allendale, Wolfdale, and Yorkfield cores, which encompassed the Intel Core 2 Duo, Intel Core 2 Quad, and Intel Core 2 Extreme series. The platform also hosted budget Intel Celeron processors and certain Intel Xeon models intended for entry-level workstation and server use, such as the Xeon 3000 series.

Chipsets and motherboards

A vast array of chipsets enabled LGA 775's flexibility, starting with the early Intel 915 and Intel 925X series. Mainstream and performance segments were served by the Intel 945, Intel 965, and the highly popular Intel P35 and Intel P45 Express chipsets. The Intel X38 and Intel X48 represented the high-end enthusiast platform. Third-party chipsets from NVIDIA (like the nForce 700 series) and ATI (such as the Radeon Xpress 200) also provided competitive alternatives with features like SLI and CrossFire multi-GPU support. Motherboard manufacturers like ASUS, Gigabyte Technology, MSI, and ASRock produced countless models, from basic office boards to feature-rich platforms like the ASUS Rampage Formula.

Successors and legacy

LGA 775 was ultimately succeeded by new sockets aligned with the Nehalem microarchitecture: the high-end LGA 1366 (for Intel Core i7 Extreme) and the mainstream LGA 1156 (for Intel Core i5 and Intel Core i7). These successors introduced integrated memory controllers and QuickPath Interconnect or Direct Media Interface, rendering the traditional FSB obsolete. The legacy of LGA 775 is profound; it was a workhorse platform that bridged a critical era in computing, supporting major architectural shifts and remaining a staple in the DIY PC building community for years. Its widespread adoption cemented the LGA form factor as Intel's standard for future desktop sockets.

Category:CPU sockets Category:Intel microprocessors Category:Computer hardware