Who makes scale-up fabric for AI data centers
Scale-up fabric (GPU-to-GPU inside the rack/pod)
The fabric linking GPUs to each other inside a single rack or pod, separate from the switching fabric that connects racks to each other.
Scale-up fabric is the shortest, highest-bandwidth network in the data center: it lets GPUs inside the same rack or pod address each other's memory directly, rather than going through the scale-out switch fabric (3.02, 3.03). It sits upstream of the copper spine and backplane cartridges (3.10) that physically wire it together and, at higher speeds, of the optics and co-packaged approaches (3.04, 3.08) being evaluated as a copper replacement. AI training and inference workloads that split a single model across many accelerators depend on this fabric scaling in lockstep with GPU count, since it sets the ceiling on how large a tightly coupled GPU domain can get. An investor should watch whether a proprietary approach keeps its lead over open alternatives being pushed by a wider industry consortium, since that split determines how concentrated the supplier base for switch chips, cables, and connectors stays as pod sizes grow.
AI delta: Larger AI models split across more GPUs per training or inference job, which raises the bandwidth and reach demanded of the scale-up fabric linking them inside a rack or pod.
Companies on this part (6)
| Company | Role | Ownership | Ticker | Price | 1d | Confidence | Note |
|---|---|---|---|---|---|---|---|
| Alphabet (Google) | manufacturer | public | GOOGL | 320 USD | -1.3% | disclosed | ICI · source |
| AMD | manufacturer | public | AMD | 517 USD | +2.2% | inferred | Infinity Fabric |
| Astera Labs | manufacturer | public | ALAB | 257 USD | +0.8% | disclosed | Scorpio X · source |
| Broadcom | manufacturer | public | AVGO | 322 USD | -0.3% | inferred | scale-up Ethernet (Tomahawk Ultra) |
| Nvidia | manufacturer | public | NVDA | 211 USD | -0.7% | disclosed | NVLink/NVSwitch · source |
| UALink consortium | manufacturer | cooperative | disclosed | members: AMD, Broadcom, Astera, Marvell, Cisco, hyperscalers · source |
Who competes here
The same table read the other way: every company above competes for scale-up fabric sockets. Confidence tags matter — an inferred placement is a lead, not a confirmed rivalry.
Seen in real machines
scale-up fabric is named in 7 of the rack teardowns and supercomputer breakdowns on this site. Each line below is a piece of that machine. The companies shown are the ones named on that line, not necessarily the maker of this part.
- Nvidia GB300 NVL72 · rack teardown
- 9× NVLink switch trays (2× NVSwitch each) — Nvidia
- AMD Helios (MI455X) · rack teardown
- Google TPU7x (Ironwood) · rack teardown
- Aurora · supercomputer
- Eagle (Microsoft Azure) · supercomputer
- In-node GPU fabric (NVSwitch and NVLink 4.0, 3.6 TB/s bisectional bandwidth between the 8 GPUs of each VM) — Nvidia
- Eos · supercomputer
- H100 GPU and in-system NVLink/NVSwitch (900 GB/s between any two GPUs in a DGX H100) — Nvidia
- MareNostrum 5 · supercomputer
- In-node GPU fabric (NVLink between the four H100 GPUs, 300 GB/s bidirectional between pairs; x16 PCIe Gen5 to the host CPUs) — Nvidia
Nearby parts
- Next in layer: Scale-out switch ASICs
- Layer: Layer 3 — Networking & interconnect
From the blog
- Part of the day: Scale-up fabric 2026-09-04
Watch
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Latest feed
- Jensen Huang warns Europe risks falling further behind US, China in AI — DigiTimes, 2026-10-23Nvidia's CEO warned that Europe faces risks of falling behind the US and China in AI advancement, calling for faster adoption and eased regulations.
- [AI Infrastructure Insight] How AI infrastructure will be designed for the future — newsroom:sk-hynix, 2026-10-22Effective real-world AI application requires improvements across faster compute, wider memory bandwidth, higher-performance networking, better storage, and more stable power infrastructure.
- Why Chip Design AI Benchmarks Must Go Beyond Functional Correctness — EE Times, 2026-10-21The increasing need for specialized architectures across various domains like physical AI and edge devices is driving a demand for custom silicon optimized for specific performance, memory bandwidth, and energy targets.
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- Interview: SEMI CEO sees US$3 trillion chip industry by 2035, as trusted partners reshape supply chain — DigiTimes, 2026-10-16SEMI's CEO predicts the semiconductor industry will achieve $2 trillion in revenue by 2035, driven by AI and quantum computing growth.
- AI’s $9-Trillion Question — HPCwire, 2026-10-15The rapid growth of the AI boom is significantly inflating costs across the supply chain, including GPUs, CPUs, memory, networking, real estate, and power infrastructure.
- AI chip competition shifts to data-center efficiency as memory, interconnect limits bite — DigiTimes, 2026-10-14The competition in AI chip development is pivoting toward data-center efficiency to overcome scaling limitations in high-bandwidth memory and interconnect speeds.
- Google data center strategic sourcing exec heads to OpenAI — Data Center Dynamics, 2026-10-13Google's strategic sourcing executive is joining OpenAI to focus on high-speed interconnects and rack power infrastructure.
- Growing pains: how distributed AI training changes the network between datacenters — The Register, 2026-10-09The article discusses how distributed AI training requirements are necessitating more robust and low-latency network architectures between data centers.
- CScale Exits Stealth with $145M to Build the Interconnect for Gigawatt-Scale AI — HPCwire, 2026-09-30CScale has raised $145 million in funding to develop high-density interconnect infrastructure specifically designed for gigawatt-scale AI data centers.
Questions about scale-up fabric
- What is scale-up fabric?
- The fabric linking GPUs to each other inside a single rack or pod, separate from the switching fabric that connects racks to each other.
- Which companies make scale-up fabric for AI data centers?
- This catalog lists 6 companies on Scale-up fabric, 5 of them with listed equity: Alphabet (Google), AMD, Astera Labs, Broadcom, Nvidia, UALink consortium.
- How does AI change demand for scale-up fabric?
- Larger AI models split across more GPUs per training or inference job, which raises the bandwidth and reach demanded of the scale-up fabric linking them inside a rack or pod.
- How reliable are these scale-up fabric supplier placements?
- The 6 placements on this part break down as 4 disclosed, 2 inferred. "disclosed" means the company or a filing says so; "reported" comes from trade press or a reference-design list; "inferred" is a taxonomy lead with no citation yet.
Sources: placements without a source URL come from the taxonomy seed and are tagged accordingly. How this data is built.· Markdown · JSON