Upscale AI Challenges Nvidia’s Scale-Up Dominance with SkyHammer Fabric and $2 Billion Valuation

The strategy becomes even more interesting when looking at Upscale AI’s relationship with Nvidia. In a surprising move, the startup has partnered with its primary rival to use Nvidia’s Spectrum-X Ethernet switches for its scale-out fabrics. This partnership highlights a growing consensus among networking veterans: while InfiniBand remains the gold standard for the absolute lowest port-to-port hop latency in HPC, Ethernet is rapidly catching up and offers superior scalability for the largest AI clusters.

Upscale AI will acquire Nvidia’s Spectrum-X ASICs to build its own scale-out switches. These will be powered by SkyOS, the company’s proprietary network operating system. SkyOS is an AI-optimized evolution of SONiC (Software for Open Networking in the Cloud), the open-source operating system originally created by Microsoft that has become a staple in hyperscaler data centers. By porting SkyOS to run on both its own SkyHammer scale-up switches and Nvidia’s Spectrum-X scale-out hardware, Upscale AI is offering a unified management and telemetry layer through its SkyCMD orchestration tool.

This unified approach allows customers to see their entire scale-up and scale-out network as a single entity. It also promises the freedom to mix and match CPUs, GPUs, and XPUs from different vendors, provided they are front-ended by a compatible DPU or NIC.

The significant hurdle remains vendor support. While the technology is promising, Nvidia has no current incentive to support SkyHammer or SkyOS as a legitimate alternative to its own NVSwitch for scale-up operations. For those heavily invested in the Nvidia ecosystem, the proprietary "walled garden" remains the only path to maximum performance.

However, the landscape looks different for competitors like AMD. Lacking a dominant proprietary switch equivalent to NVSwitch, AMD is increasingly dependent on third-party innovators to provide the scale-up networking required for its own AI accelerators. There is already speculation that if Upscale AI’s technology proves successful in the field, it could become an acquisition target for a company like AMD, looking to secure its own scale-up fabric and diversify its revenue streams.

Ultimately, the battle for the heart of the AI data center will be won by the architecture that can best balance raw performance with economic reality. Nvidia can always choose to increase the radix of its NVSwitch ASICs to flatten its networks, though likely at the cost of bandwidth per port. Alternatively, it could eventually adopt an industry-standard scale-up network for its inference-focused products while keeping training locked down. As the first generation of Ultra Ethernet Consortium-compatible switches nears the market, the long-standing reign of InfiniBand is facing its most serious challenge yet. Whether Upscale AI’s SkyHammer can truly act as the "universal glue" for the next generation of XPUs remains to be seen, but with $500 million in backing and a focus on predictable performance, they are positioned to be a major player in the unfolding AI infrastructure war.