Socket G1
Socket G1, also known as rPGA 988A, is a pin grid array (PGA) CPU socket designed by Intel for mobile processors, featuring 988 pins arranged in a staggered grid to support removable packaged chips.[1] Introduced in September 2009, it was developed to accommodate the first-generation Intel Core family of microprocessors based on the Nehalem and Westmere microarchitectures, enabling high-performance computing in laptops.[1] This socket supports a range of dual-core and quad-core processors, including Intel Core i3, Core i5, Core i7, Pentium, and Celeron mobile variants fabricated on 45 nm and 32 nm processes.[1] Compatible processors operate with thermal design powers (TDP) typically between 18 W and 55 W, featuring integrated Intel HD Graphics in dual-core models that can drive up to two independent displays.[1] Memory support varies by processor: entry-level models handle DDR3 up to 800 MHz across two channels, while higher-end Core i5 and i7 dual-core chips support up to 1066 MHz, and quad-core variants reach 1333 MHz.[1] Socket G1 interfaces with Intel's 5 Series chipsets, such as the HM55, PM55, and QM57, via a Direct Media Interface (DMI) and PCI Express 2.0 lanes for connectivity and expansion.[1] It was commonly used in business and professional laptops from manufacturers like Dell (e.g., Latitude E6510) and HP (e.g., EliteBook 8540p), providing upgradeability for mobile workstations during its era.[1] The socket was succeeded by Socket G2 (rPGA 988B) in 2010 for second-generation Core processors, though G1 remains incompatible with G2 due to keying differences.[2]History
Development Background
Intel developed Socket G1 to support the mobile implementations of its Nehalem microarchitecture, marking a significant evolution in portable processor design by integrating key system components directly onto the CPU die. This approach addressed the limitations of the predecessor Socket P, a 478-pin micro-FCPGA interface used for Core 2 Duo mobile processors, which constrained power delivery and signal routing for emerging higher-performance requirements in laptops. By succeeding Socket P, Socket G1 enabled more robust electrical interfaces necessary for advanced features like the integrated memory controller and Direct Media Interface (DMI), facilitating greater scalability across mobile product lines. The adoption of the rPGA form factor in Socket G1 represented Intel's strategic shift for mobile processors, prioritizing enhanced integration and serviceability in compact laptop chassis. Unlike the mPGA design of Socket P, where pins were on the processor package, rPGA placed spring-loaded pins on the socket itself, allowing for zero-insertion force installation and easier field replacement without risking damage to fragile components. This configuration contributed to better overall thermal management in thermally constrained environments. As the mobile counterpart to desktop sockets LGA 1156 and LGA 1366, Socket G1 was engineered to deliver Nehalem's performance benefits—such as up to 8 MB of shared L3 cache and dynamic power scaling—to portable devices, overcoming the power and performance bottlenecks of prior architectures like Penryn. Key design goals focused on enabling quad-core configurations in high-performance laptops through refined energy efficiency mechanisms, including stricter power thresholds and support for DDR3 memory via the on-die controller, which boosted bandwidth while minimizing system power draw. These advancements allowed Intel to optimize Nehalem for power-constrained scenarios without sacrificing computational capabilities.Release and Evolution
Socket G1 was initially released on September 23, 2009, alongside the launch of the first compatible processors from Intel's Clarksfield family, including the Core i7-720QM, i7-820QM, and i7-920XM.[3] These quad-core mobile CPUs marked the socket's entry into high-performance computing for laptops, supporting the Nehalem architecture's transition to mobile platforms.[4] Subsequent processor releases expanded Socket G1's lineup, with additional Clarksfield models such as the i7-740QM and i7-940XM introduced on June 21, 2010.[5] Earlier in the year, on January 7, 2010, Intel launched Arrandale-based processors compatible with the socket, including the Core i7-620M and i5-520M, which incorporated Westmere architecture improvements like integrated graphics on a 32 nm process.[6] These additions extended the socket's versatility for dual- and quad-core configurations in mobile systems. Socket G1 gained adoption in high-end mobile workstations and gaming laptops between 2009 and 2011, powering devices such as the Dell Precision M6400 workstation and Alienware M17x gaming notebook.[7] Support for the socket began to phase out in 2011 as Intel shifted to Socket G2 with the Sandy Bridge generation, though some compatible systems continued production into 2012.Supported Processors
Clarksfield Family
The Clarksfield family consists of quad-core mobile processors introduced by Intel as part of the first-generation Core i7 lineup, designed specifically for high-performance laptops using Socket G1. These processors, built on the 45 nm process technology, feature four physical cores with Hyper-Threading Technology enabled, allowing for eight logical threads to handle demanding multitasking workloads. They include an integrated dual-channel memory controller supporting DDR3-1066 memory (with some models extending to DDR3-1333), and thermal design power (TDP) ratings ranging from 45 W to 55 W to balance performance and power efficiency in mobile environments.[8] The family launched on September 23, 2009, with initial models including the Core i7-720QM, i7-820QM, and i7-920XM, followed by expansions on June 21, 2010, adding the Core i7-740QM, i7-840QM, and i7-940XM. These processors targeted high-end mobile computing applications, such as video editing, 3D rendering, and professional content creation in laptops and mobile workstations, where their Turbo Boost Technology could dynamically increase clock speeds for intensive tasks.[9][10] Key models in the Clarksfield family are summarized below, highlighting their base and turbo frequencies along with L3 cache sizes:| Model | Base Frequency | Turbo Frequency | L3 Cache | TDP |
|---|---|---|---|---|
| i7-720QM | 1.60 GHz | 2.80 GHz | 6 MB | 45 W |
| i7-740QM | 1.73 GHz | 2.93 GHz | 6 MB | 45 W |
| i7-820QM | 1.73 GHz | 3.06 GHz | 8 MB | 45 W |
| i7-840QM | 1.86 GHz | 3.20 GHz | 8 MB | 45 W |
| i7-920XM | 2.00 GHz | 3.20 GHz | 8 MB | 55 W |
| i7-940XM | 2.13 GHz | 3.33 GHz | 8 MB | 55 W |