A public research surface · updated continuously
The AI buildout will be won by whoever owns the chokepoints.
HBM stacks, CoWoS packaging, EUV optics, gigawatts of power, optical interconnect, liquid cooling. Compute Bottlenecks maps the physical supply chain behind every GPU cluster — and the listed companies that own each choke. Own the strait, not the tanker.
60 names tracked · 10 chokepoints · free, no login
The chokepoints
I
HBM & memory bandwidth
Every accelerator is bandwidth-starved; high-bandwidth memory comes from three companies and is sold out years ahead.
MU · 000660.KS · SSNLF · CAMT · ONTO · FORM · BESIY
II
Advanced packaging & CoWoS
The GPU shortage has repeatedly been a packaging shortage: 2.5D/3D interposer and hybrid-bonding capacity, not wafer starts, sets accelerator output.
TSM · AMKR · ASX · BESIY · ONTO · CAMT
III
Lithography & EUV optics
Leading-edge logic and DRAM both route through one EUV toolmaker — and the single-source optics and laser chain inside it.
ASML · ZEISSSMT · TRUMPF · KLAC · LRCX · AMAT
IV
Leading-edge foundry
Every frontier accelerator is fabbed by one company, mostly in one geography; the alternatives are years behind.
TSM · ASML · INTC · ZEISSSMT · SSNLF · SHECY
V
Power, grid & generation
Datacenter interconnect queues and transformer lead times are measured in years; gigawatts are the new wafer starts.
CEG · VST · TLN · GEV · ETN · PWR · HUBB · CLF
VI
Liquid cooling & thermal
Rack densities past 100 kW make direct-liquid cooling mandatory — and the cold-plate, CDU and rear-door supply chain is thin.
VRT · MOD · NVT · ECL · SBGSY · COOLIT · BOYD
VII
Optical interconnect & networking
Scaling clusters beyond a rack is an optics problem: 800G/1.6T transceivers, co-packaged optics, and the lasers and DSPs inside them.
COHR · LITE · FN · MRVL · CRDO · AAOI · ANET
VIII
Substrates, resist & wafer materials
ABF substrates, advanced photoresists, and 300mm silicon are quiet few-supplier markets sitting under every chip.
IBIDF · AJNMY · SHECY · SUOPY · ENTG · MKKGY · FUJIY · SHWDF · TOKCF
IX
Accelerators & the capex layer
The visible layer: accelerator designers and the hyperscaler capex programs that every other choke feeds.
NVDA · AVGO · AMD · GOOGL · AMZN · META · MSFT
X
Private giants & exposure vehicles
OpenAI, Anthropic, xAI — the AI cap tables without tickers, and the listed and quasi-listed paths into them.
MSFT · AMZN · GOOGL · CRWV · SFTBY · OPENAI · ANTHROPIC · VCX
Latest brief · 2026-10-27
A broadening optical-interconnect rally carried the AI-infrastructure complex, led by Lumentum, while advanced-packaging name Amkor was the one rung that broke lower.
The leader was Lumentum (LITE), up 8.2% to $818.10 on the optical-interconnect chokepoint — the lasers and high-speed transceivers that gate bandwidth between accelerators in an AI datacenter. The move was part of a broadening optics rally rather than a single print: demand for 800G and 1.6T transceivers remains supply-constrained, with capacity reportedly booked well into the back half of the decade. The rally was not isolated to Lumentum — Applied Optoelectronics (AAOI) rose 6.6% to $71.94 and Coherent (COHR) added 5.8% to $221.50 — which is the tell that this was the interconnect strait re-rating as a group, the physical layer that an accelerator cluster cannot scale past without.
The laggard was Amkor (AMKR), down 6.3% to $36.81 on the advanced-packaging chokepoint — the outsourced assembly and test (OSAT) layer that gates chiplet integration and HBM co-packaging for the AI build-out. There was no clean session catalyst, and the decline extends an overhang that has dogged the name since its summer guidance: heavy multi-year capex plans against a softer near-term outlook. With Amkor's Q3 results due shortly, the packaging rung is the basket's swing risk — it is the step in the flow with the least spare capacity and the most concentrated customer base.
Elsewhere the enabling rungs mostly firmed. On hbm-memory, Micron (MU) rose 3.0% to $903.70 and SK Hynix (000660.KS) added 5.2% in its Seoul session; the leading-edge anchors held — TSMC's ADR (TSM) +1.4% to $424.37, NVIDIA (NVDA) +2.4% to $216.00, Broadcom (AVGO) +2.3% to $329.17 and Marvell (MRVL) +2.3% to $233.78. The power-grid rung, which had stayed soft through last week's unwind, rebounded: GE Vernova (GEV) +4.9% to $855.12 and Vertiv (VRT) +2.8% to $199.78, the clearest sign the datacenter-power trade found a bid. The downside outliers were the materials name Cleveland-Cliffs (CLF) −3.7% to $13.38 and the hyperscaler Meta (META) −1.9% to $630.56.
The forward calendar is thin into year-end. The Intel 14A external-customer decision window opens December 31 — the first real read on whether a second leading-edge foundry option becomes viable — and Ibiden's AI-substrate ramp runs through FY2027 on the substrates-materials rung. Until the packaging and power straits show spare capacity, they, not raw accelerator demand, remain the session-to-session constraint on the complex.