Is Vera Rubin on Track? Jensen Huang Says Yes, HBM4 Constraints and Kyber Delay Fuel Doubt

What Sparked the Delay Concerns

Several factors fueled reports of potential delays:

• HBM4 memory supply constraints — Trendforce reported that Rubin-series GPU shipments in 2026 were expected to drop from 29% to 22% of Nvidia's high-end mix, citing HBM4 supply delays from SK Hynix and Samsung .
• Packaging and substrate bottlenecks — Analysts at Computex 2026 flagged that 'packaging and substrate constraints remain the practical limiter' for the aggressive Vera Rubin ramp .
• Broader industry skepticism — Elon Musk cautioned in January 2026 that Rubin chips would take months to scale to real-world deployment, despite the CES hype .
• A separate Kyber rack-system delay — CNBC reported on July 6, 2026, that Nvidia's next-gen AI rack system (Kyber) was delayed to 2028, adding to concerns about Nvidia's breakneck annual cadence colliding with manufacturing limits .

Key Production & Timeline Details for Vera Rubin

The platform uses approximately 500 billion transistors on TSMC's N2 process, HBM4 memory at 13 TB/s bandwidth, NVLink 6 at 5 TB/s bidirectional, and delivers up to 8 exaFLOPS per rack . Nvidia's official website states the platform is 'ramping into full production, with Taiwan's top server makers and global supply chain leaders manufacturing at scale' .

Broader Context: Nvidia's Production Track Record

Vera Rubin delay concerns sit against a pattern of production challenges:

• Blackwell delays (2024) — The Information reported in August 2024 that Blackwell GPUs were delayed by 3+ months due to a design flaw discovered late in the process . Nvidia acknowledged production issues and said it revamped part of the chip's manufacturing process . Nvidia later fixed the issue and shipped 'several billion dollars' worth' in Q4 2024 .
• Persistent supply-demand imbalance — Reuters reported in November 2024 that Nvidia's demand would outstrip supply for several quarters in fiscal 2026 .
• Blackwell still dominant in 2026 — Even as Rubin ramps, analysts at iConnect007 projected in April 2026 that Blackwell would still drive over 70% of Nvidia's high-end GPU shipments in 2026, with Rubin's share limited by HBM4 constraints .

Bottom line: Huang is publicly adamant that Vera Rubin is on track with production already underway. The credible counter-evidence centers on HBM4 memory bottlenecks and packaging constraints that could slow the volume ramp, rather than a full halt. The separate Kyber rack delay (to 2028) and the history of Blackwell's teething problems add to the market's sensitivity to any Nvidia supply-chain signals.