Intel LGA 1851 socket specification exposures
Yesterday, Igor’s LAB procured an internal presentation from Intel, showcasing the projected performance of the desktop version of Arrow Lake-S, which is anticipated to outpace Raptor Lake-S by approximately 6% to 21% across varied projects. The presentation also divulged further details about Arrow Lake-S, such as the differing Z-heights of the LGA1851 socket.
Today, Igor’s LAB unveiled the technical specifications of the LGA 1851 socket, encompassing facets from pin features to mechanical attributes, information that is crucial for manufacturers of heat sinks.
In addition to providing a PCIe 5.0 x16 slot for a standalone graphics card, Arrow Lake-S will also include a PCIe 5.0 x4 channel for SSDs. Moreover, Intel will retain a PCIe 4.0 x4 channel for SSDs that is directly linked to the CPU. From the layout of the pins, it is evident that the area for PCIe connections has been significantly enlarged. As Intel plans to segment the chipsets, it is plausible that only the highest-level Z-series will offer a PCIe 5.0 x4 M.2 slot.
In comparison, the AM5 platform appears more robust with a 16+4+4 combination of PCIe 5.0 channels. When paired with the Ryzen 7000 series, the 16 standalone PCIe 5.0 channels for graphics cards can be further split into an 8+4+4 combination, providing an array of options.
Contrary to yesterday’s assertions, Igor’s LAB contends that based on existing data, the Z-height distance should remain constant, with the distance between the top of the circuit board and the Integrated Heat Spreader (IHS) also unchanged. Although the new socket has seen an increment in the number of pins, its physical specifications essentially mirror those of the LGA 1700 socket. However, the installation pressure has nearly doubled, increasing from 489.5 N to 923 N. This implies that even with a constant Z-height, different mounting brackets may be necessary.
Given the substantial installation pressure, current CPUs may experience bending over prolonged usage. As installation pressure continues to escalate, it remains uncertain how manufacturers of heat sinks will tackle these issues. On a positive note, the official release of the specific LGA 1851 socket remains in the distant future, providing manufacturers of heat sinks ample time to optimize the design of their mounting brackets.
