SanDisk Debuts 256TB UltraQLC Enterprise SSDs
Purpose-built density for AI data lakes and hyperscale, with a 128TB companion drive
SanDisk introduced its UltraQLC enterprise platform with a 256TB NVMe SSD and a 128TB SN670 variant, pairing new 2-Tb BiCS8 QLC NAND with controller-level innovations to deliver extreme capacity with predictable performance; first U.2 models ship in 1H26.
Milpitas, CA – August 5, 2025 (Updated: September 16, 2025) — SanDisk unveiled an enterprise SSD platform, UltraQLC, headlined by a 256TB NVMe drive designed for maximum storage density in AI and cloud environments. The announcement, made during FMS 2025, also includes the SN670 128TB model on the same architecture and confirms U.2 availability in the first half of 2026, with additional form factors to follow.
UltraQLC departs from conventional QLC implementations by writing directly to QLC rather than relying on a pseudo-SLC buffer—aimed at consistent, power-loss-safe writes over long transfers common to AI ingest and data-lake workloads. SanDisk also detailed platform-level power and reliability features intended to sustain performance at extreme capacities.
Independent coverage characterized the 256TB model as one of the industry’s first drives at this capacity and noted the platform’s focus on density and consistency over bursty cache behavior—aligning with hyperscale requirements.
As we move into the next phase of the AI era, flash storage is becoming a critical enabler of intelligent, high-performance workloads.
said Khurram Ismail, Chief Product Officer at SanDisk.
SanDisk’s FMS presence included a keynote on August 6 at 11:40 AM PT and live demos at Booth #607, underscoring the company’s bid to pair very-high capacities with predictable economics for hyperscale and large enterprise deployments.
What’s new in UltraQLC (highlights)
- 256TB1 UltraQLC NVMe SSD and 128TB1 SN670 on the same platform; U.2 initially, more form factors later (shipping 1H26).
- Direct Write QLC: eliminates SLC buffering with power-loss-safe first-pass writes for consistent long-duration transfers.
- BiCS8 2-Tb QLC die for higher density at compact die sizes.
- Dynamic Frequency Scaling (UltraQLC power optimization): projected ~10% higher performance at a given power level (internal testing).
- Data Retention profile: projected ~33% reduction in retention-related recycles (internal testing) to improve reliability and energy efficiency.
- Positioning: density-first SSDs for AI data lakes, ingest/prep, and hyperscale cloud; among the first 256TB NVMe SSDs reported publicly.
Coverage from Tom’s Hardware emphasized the platform’s strategy: foregoing pseudo-SLC caches can reduce short-burst speeds versus typical cached designs, but avoids cache cliff effects and keeps performance steady over hours-long writes—a better fit for large sequential AI workloads. SanDisk lists first-half-2026 availability for both 128TB and 256TB models.
About SanDisk
SanDisk (Nasdaq: SNDK) designs flash-based storage solutions and advanced memory technologies for consumers and enterprises worldwide. The UltraQLC platform reflects the company’s push to pair very high capacities with efficiency and reliability for AI-scale infrastructure.
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