Arm details AGI server CPU with two 70-core N3P chiplets and 2 TB/s UCIe fabric link

Arm Reveals AGI CPU Details

Arm disclosed further technical specifications for its AGI data center CPU at Hot Chips 2026. This follows an earlier announcement where key specifications were revealed without extensive technical details. Arm confirmed the processor's design is working as planned and provided planned configurations, stating it is on track for commercial shipments starting in late 2026.

Core and Memory Specifications

The AGI is a dual-chiplet data center processor, configurable with 64, 128, or 136 Neoverse V3 cores operating between 2.80 GHz and 3.70 GHz. Each core includes two 128-bit vector engines and 2MB of L2 cache, with up to 272 MB of system-level cache. Each CSS V3 chiplet contains 70 V3 cores and a six-channel memory subsystem supporting up to 3 TB of DDR5-8800 memory per chiplet, totaling 6 TB per socket.

Interconnect and I/O

The two chiplets connect using 16x16 UCIe macros running at 32 GT/s, providing an aggregated bandwidth of 2 TB/s. For I/O, the AGI CPU offers 96 PCIe 6.0 lanes utilizing the CXL 3.0 protocol for memory expansion, four PCIe 4.0 lanes, and I3C, I2C, and SPI interfaces. The CPU has a thermal design power of 300W.

Design Philosophy

Arm's AGI employs two largely self-contained SoC chiplets manufactured on TSMC's N3P technology, integrating both compute and I/O on the same die. This contrasts with the heterogeneous multi-chiplet designs used by AMD, Intel, and Nvidia, which typically separate compute and I/O into different chiplets. Arm's approach aims to combine high core counts with substantial memory bandwidth.