Arm launches Neoverse CSS N4 'Ranger' platform with up to 128 cores on TSMC N3P

Next-Gen Neoverse CSS N4 Platform Unveiled

Arm has announced its next-generation Neoverse CSS N4 platform, known as 'Ranger,' designed for cloud and data center applications. This new platform allows for up to 128 Neoverse N4 cores per die and utilizes TSMC's N3P process technology. The Compute Subsystem (CSS) program enables customers to customize chip designs based on Arm's IP, including core count, cache size, and I/O configurations.

Architectural Enhancements and Scalability

The Neoverse CSS N4 platform supports core counts ranging from eight to 128 Neoverse N4 cores, with clock speeds up to 3.8 GHz. It can scale beyond 128 cores through multi-chiplet and multi-socket designs, incorporating UCIe for chip-to-chip interconnects. Memory support includes DDR5 or LPDDR6, with up to 256 MB of L3 cache per die, 2 MB of L2 cache per core, and 64 KB each of L1 instruction and data cache per core. For I/O, it provides up to 128 lanes of PCIe 7/6 and CXL 4.0.

Performance Improvements

The Neoverse CSS N4 represents a substantial upgrade from the Neoverse CSS N2 platform, which was limited to 64 cores, 1 MB of L2 cache, and 64 MB of L3 cache, along with DDR5/LPDDR5 and 64 PCIe 5.0/CXL lanes. Arm states that the Neoverse CSS N4 delivers twice the socket performance of Neoverse N3, 1.25 times performance per watt, and 1.75 times the memory bandwidth when configured with 128 cores running at 3GHz and 2MB of L2 cache per core.

Target Workloads and Market Impact

Arm's N-series cores are optimized for performance per watt, making them suitable for less-performant accelerators and cloud-based workloads. Previous N-series cores have been deployed in products like Intel's IPU Adapter E2100 (Neoverse N1) and Microsoft's Azure Cobalt 100 (Neoverse N2). The Neoverse CSS N4 platform is expected to continue this trend, providing a foundation for energy-efficient solutions in data centers and cloud infrastructure, complementing the high-performance V-series cores used in CPUs like Nvidia's Grace and AWS Graviton chips.