Socket 479

Socket 479. It is a CPU socket interface specification used by Intel Corporation for several of its mobile processors during the mid-2000s. While sharing its pin count with the desktop Socket 478, it is electrically and physically incompatible, designed specifically for the Pentium M and related Centrino platform components. The socket's introduction was pivotal for the evolution of mobile computing, enabling more powerful and energy-efficient notebook designs.

Technical specifications

The interface operates with a front-side bus speed of either 400 or 533 MT/s, supporting key technologies like Enhanced Intel SpeedStep Technology for dynamic power management. It was designed to work with processors utilizing a 90 nm manufacturing process, which significantly improved performance per watt. The socket specification was integral to the Centrino platform, which also mandated specific Intel wireless cards and chipsets for certification. This holistic design approach by Intel was aimed at optimizing battery life and wireless connectivity in portable systems.

Compatible processors

The primary CPUs for this interface are the Pentium M family, including the Banias and Dothan cores, and the lower-cost Celeron M derivatives. It also officially supports the first-generation Core microarchitecture processors, namely the Core Solo and Core Duo (codenamed Yonah). Notably, some motherboard manufacturers created adapters to allow these mobile processors to be used in select desktop boards, such as those using the ATI Radeon Xpress 200 chipset. However, the socket is not compatible with the subsequent Core 2 Duo (Merom), which required the newer Socket M.

Motherboard chipsets

The socket was paired with several key mobile chipsets from Intel, most prominently the 855 series (Alviso) and the 915M series (Alviso). These chipsets provided support for DDR or DDR2 SDRAM, PCI Express graphics via the ATI Mobility Radeon or NVIDIA GeForce Go series, and integrated graphics through the Intel GMA series. Other chipsets that supported Socket 479 include the 865GV and the ATI Radeon Xpress 200M. The chipset pairing was crucial for enabling advanced features like Intel High Definition Audio and SATA storage interfaces in contemporary laptops.

Physical design and pinout

The socket uses a 479-pin PGA layout, but processors were also available in a 479-ball Micro-FCBGA package for permanently soldered applications in ultra-thin designs. The pinout is deliberately different from the desktop Socket 478 to prevent incorrect installation, though the processors share a similar physical appearance. The voltage regulator for the CPU was typically located on the motherboard, a design common to mobile platforms to save space within the processor package itself. This design philosophy emphasized the compact and thermally constrained environment of mobile computers.

Historical context and market position

Socket 479 arrived with the launch of the Pentium M and the Centrino brand in 2003, a direct response to the competitive pressure from AMD's mobile processors and the need for better performance in the growing notebook market. It represented a clear break from the NetBurst architecture of the desktop Pentium 4, instead leveraging the more efficient P6 microarchitecture derived from the Pentium III. This shift, championed by Intel's design team in Haifa, Israel, was instrumental in combating the Transmeta Crusoe and solidifying Intel's dominance in mobile computing throughout the era of Microsoft Windows XP. Its success directly paved the way for the Core brand and the subsequent transition to Socket M.

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