Built for Vera Rubin, NVIDIA Spectrum-6 Arrives in Gigascale AI Factories

AI has entered the gigascale era.

The world’s most advanced AI factories are bringing together hundreds of thousands of GPUs and CPUs to train frontier models, power agentic AI and generate intelligence at unprecedented scale. At this level, networking becomes a critical computing power multiplier in driving token generation.

Marking a networking milestone, NVIDIA Spectrum-6 — a 102.4-terabit-per-second Ethernet switch system delivering 2x the capacity of previous-generation systems and built as part of the NVIDIA Vera Rubin platform — is arriving across the world’s gigascale AI factories.

Spectrum-6 anchors the next generation of the NVIDIA Spectrum-X Ethernet platform, delivering the bandwidth, scale and intelligence needed to operate an AI factory as one end-to-end computing system.

Leading AI Builders Move First

The world’s leading AI infrastructure builders — including CoreWeave, Microsoft, Nebius, SpaceXAI and Tesla — will be among the first to bring in Spectrum-6 to accelerate their AI factories.

For cloud providers, Spectrum-6 means more compute capacity can operate as a unified, high-performance resource, helping customers train models and deploy inference services faster.

“CoreWeave is built for the most demanding AI workloads, and networking is central to delivering that performance at scale,” said Min Jun, director of product for networking at CoreWeave. “Bringing NVIDIA Spectrum-6 and liquid-cooled Spectrum-X Ethernet infrastructure into our AI factories will help us deliver the bandwidth, resilience and efficiency customers need to train frontier models and deploy inference faster.”

“At gigascale, performance comes down to coordination: keeping every GPU in lockstep so one slow link doesn’t stall an entire job,” said Laurelle Roseman, vice president of global partnerships at Nebius. “That’s what NVIDIA Spectrum-6 goes after, and why we brought it in early — a fabric that stays fast and resilient as our customers’ most demanding workloads scale.”

For AI pioneers building their own infrastructure, Spectrum-6 means more GPUs working in lockstep, higher utilization during demanding collective operations and greater resilience for long-running jobs.

Across use cases, the outcome is faster time to results and better economics at extraordinary scale.

CoreWeave, Microsoft and Nebius will be among the first providers to deploy NVIDIA Vera Rubin-based infrastructure with Spectrum-6, extending access to the platform across a broad community of developers, startups and enterprises.

AI Performance Is a Network Problem

Peak GPU performance alone no longer predicts the performance of an AI factory.

Large-scale training and inference workloads depend on thousands of accelerators exchanging data continuously. Collective communications are the fundamental operations that synchronize work across GPUs and generate intense east-west traffic, often with many systems transmitting simultaneously.

Ethernet was designed primarily for enterprise applications and north-south traffic moving between users, servers and storage. It wasn’t created for the synchronized, collective-heavy communication patterns of gigascale AI.

Spectrum-X Ethernet changes that. Purpose-built for AI, it transforms Ethernet into a high-performance scale-out fabric engineered to keep every GPU fed with data.

The Next Generation of Spectrum-X Ethernet

The Spectrum-6 switch chip combines with the NVIDIA ConnectX-9 SuperNIC to form the next generation of Spectrum-X Ethernet, and is engineered as part of NVIDIA Vera Rubin, bringing together the NVIDIA Vera CPU, Rubin GPU, NVLink 6 Switch, ConnectX-9 SuperNIC, BlueField-4 DPU and Spectrum-6 Ethernet switch.

Spectrum-6 supports both pluggable and co-packaged optics form factors. In addition, Spectrum-6 offerings support liquid cooling, enabling a comprehensive, end-to-end cooling approach for the entire AI factory while increasing network power efficiency.

Unlike off-the-shelf Ethernet, the NVIDIA Spectrum-X Ethernet networking platform for AI factory scale-out combines intelligent switches, NVIDIA ConnectX-9 SuperNICs and full-stack networking software, all engineered together for AI. The platform’s advanced features continuously optimize how traffic moves through the fabric.

In addition, NVIDIA Spectrum-X technology intelligently balances traffic across available paths, rapidly bypasses failures and precisely recovers when data traveling across a network fails to reach its destination. Plus, support for open network operating systems and a choice of RDMA transport models gives AI builders flexibility without compromising performance.

Spectrum-X Ethernet is inherent to NVIDIA’s vertically integrated, horizontally open approach: codesigning silicon, systems and software across the full computing platform while supporting standard Ethernet, open network operating systems, open protocols and a broad ecosystem of cloud providers, system makers and infrastructure partners. Instead of needing to assemble a collection of parts and optimize them afterward, customers gain a complete AI factory platform designed to deliver the fastest time to train and the lowest cost per token.

Demonstrating this approach, Spectrum-X Ethernet delivers up to 1.6x higher AI networking performance than off-the-shelf Ethernet and sustains up to 95% network efficiency across deployments exceeding 100,000 GPUs.

Hardware-accelerated Spectrum-X multiplane topologies reduce the number of switches required for data centers by 1.7x to further accelerate network efficiency. Further layering on the benefits achieved via Spectrum-X Ethernet Photonics, including 5x higher power efficiency and 10x improved mean time between incidents, network fabric enhancements continue to deliver workload accelerations beyond component-level optimization.

Learn more about the NVIDIA Spectrum-X Ethernet platform.