Zhihu Article Review: Is SanDisk's HBF a Real Breakthrough or a Bubble?
Fact-checking @Moenova's analysis on SanDisk stock and HBF technology
Original Claims
Zhihu user @Moenova argues:
- SanDisk, AMD, and Intel stock prices will be pulled to the same level as NVDA
- SanDisk is攻克 the high-bandwidth memory bottleneck; once broken through, “SanDisk = Micron + SK Hynix + Samsung”
- HBM may reach 192GB, HBF may reach 1TB~4TB
- Intel + SpaceX will push humanity toward becoming an interstellar civilization
Data Verification
SanDisk Stock: Gains Are Real
- Spun off from Western Digital, started independent trading Feb 2025 at ~$48
- Closed at $1,716.36 on June 2, 2026
- Gain from IPO: 3,500%+
- 2025 full-year gain: 578.5%
The numbers are accurate. The driver is real earnings: Q3 FY2026 revenue grew +251% YoY.
HBF Technology: Real, But Misunderstood
HBF (High Bandwidth Flash) is a genuine technology direction:
- Aug 2025: SanDisk and SK Hynix agreed to co-develop and standardize HBF
- Built on NAND Flash with HBM-like stacking (CBA technology)
- Official data: within 2.2% of unlimited-capacity HBM performance in large-capacity scenarios
- Samples expected H2 2026, AI inference device sampling in early 2027
- Small-scale commercial deployment 2027-2028, widespread adoption post-2030
But the article confuses critical concepts:
HBF and HBM are complementary, not substitutes:
| Dimension | HBM | HBF |
|---|---|---|
| Underlying tech | DRAM | NAND Flash |
| Latency | Nanoseconds | Microseconds |
| Capacity | GB-scale | TB-scale |
| Use case | AI training | AI inference storage layer |
| Maturity | Mass production for years | Sample stage |
The claim “SanDisk = Micron + SK Hynix + Samsung” is incorrect. These three are core HBM suppliers with 95%+ market share. SanDisk only has the NAND line — an order of magnitude difference in scale.
Valuation Analysis
| Metric | Value |
|---|---|
| Current P/E (TTM) | 48.6x |
| Forward P/E | 9.98x |
| Market Cap | ~$200B |
| Q3 Revenue Growth | +251% YoY |
Forward P/E at 9.98 indicates analysts expect explosive earnings growth. But the 3,500% gain has already priced in substantial optimism, leaving little room for error.
Score: 6.5/10
Credit:
- HBF is a real technology direction, not vaporware
- SanDisk stock gains are factually accurate
- Correctly identifies the memory sector opportunity
Debits:
- Confuses HBM and HBF — two completely different technology paths
- “SanDisk = Micron + SK Hynix + Samsung” equation doesn’t hold
- “Intel + SpaceX → Dyson Sphere → Interstellar civilization” is sci-fi, not investment analysis
- Conclusions are overly aggressive with insufficient risk disclosure
Conclusion
HBF is a real technology direction, and SanDisk’s positioning is forward-looking. But “the next NVIDIA” is premature — NVIDIA defined AI computing from scratch, while SanDisk is making incremental innovation in the memory赛道. Different magnitude.
Chasing at current levels carries meaningful risk. Waiting for HBF sample data before reassessing is more prudent than going all-in now.