What Is Socket 775?

Socket 775 is better known as Land Grid Array (LGA) 775 or Socket T, and it is a central processing unit (CPU) socket from semiconductor manufacturer Intel Corporation. It marked the company’s first LGA-based socket. Although several similar sockets have followed it since its 2004 debut, Socket 775 remains the most popular CPU socket under this form factor category. It supports some processors from the Pentium, Core, Celeron and Xeon brands. The three digits represent the number of pin contacts it has.

The LGA designation is for a socket that has pins on it, rather than on the processor that it is meant to accommodate for data transmission with the motherboard and physical support. The gold-plated pins of Socket 775 are neatly arranged in four rows that form a grid measuring 1.29 by 1.18 inches (33 by 30 millimeters), thus its "grid array" category. The grid is placed on a square-shaped structure that measures 1.48 square inches (37.6 square mm), and it has a 0.6-by-0.55-inch (15-by-14-mm) section in the center cut out.

Socket 775 falls under the LGA subcategory called flip-chip land grid array (FCLGA). This denotes the processor installed in such a way that its die, which is the wafer of semiconductor material that houses its core(s), or processing unit(s), has its back facing upward. This makes it possible for a heatsink to be introduced to the CPU, which dissipates heat and consequently promotes energy efficiency and prevents malfunction.

Intel introduced Socket 775 to replace Socket 478 for the Intel Pentium 4, which at the time represented the company’s flagship CPU brand. Compatibility was also extended to the higher-level yet higher power-consuming variants of the Pentium 4 subcategorized as the Pentium D and Extreme Edition. When the Core 2 supplanted Pentium as Intel’s premier brand, the company also granted some of its entries compatibility with Socket 775. Other CPUs that work with the component are members of the low-end Celeron; the Xeon, which is aimed at workstations, servers and embedded systems; and the Pentium Dual-Core, which represented the Pentium’s relegation to mid-range status.

Socket 775 accommodates CPUs with data transmission speeds of 533, 800, 1,066, 1,333 and 1,600 megahertz (MHz). This translates into 5.33 million, 8 million, 1.06 billion, 1.33 billion and 1.6 billion transfers per second. The processor speed ranges of the compatible processors are Pentium 4 at 2.66 to 3.73 gigahertz (GHz), Pentium Dual-Core at 1.6 to 3.73 GHz, Core 2 at 1.8 to 3.33 GHz, Xeon at 1.86 to 3.16 GHz and Celeron at 1.6 to 3.6 GHz.