AI Gold Rush: Two of the world's "big three" memory manufacturers began collaborating on a new memory standard for accelerating AI workloads in 2025. Now, the first technical specification for High Bandwidth Flash memory is ready for major data center manufacturers to experiment with.
A year ago, SanDisk and SK Hynix announced a collaboration to develop a common standard for the High Bandwidth Flash (HBF) project. The new type of memory is designed to improve performance and power efficiency in AI data centers and can now be implemented in new data center projects thanks to the newly announced HBF technical specification.
The first HBF technical specification is part of the Open Compute Project, which means it should be freely available for adoption in custom data center projects or server designs. SanDisk and SK Hynix are the main contributors to the new specification, but other major AI industry players including Google and Tenstorrent have joined the standardization process with their own ideas and technology validation procedures.
The HBF specification lays out the foundation for an HBF-ready rack or data center, defining the system interface, electrical requirements, and other technical guidelines needed to integrate HBF into a custom design. Furthermore, the specification includes "basic" performance expectations, the xPU-HBF host interface, and additional details on reliability and packaging for an HBF die stack. A software user guide covering read and write operations is also part of the specification.
SanDisk developed HBF memory to combine the large storage capacity of NAND flash chips with the high-bandwidth data rates typically associated with High Bandwidth Memory products. The new HBF chips can vertically stack eight HBF layers, with a theoretical capacity of up to 4TB per chip.
SanDisk CTO Alper Ilkbahar explained that HBF memory was conceived to meet the unprecedented memory demands of AI inference workloads and accelerators. Thanks to the new specification, system builders and data center operators now have a "practical path" to placing high-capacity memory and compute units or GPUs closer together. This significant milestone could also enable the creation of more flexible AI architectures.
SanDisk and SK Hynix chose the OCP as a way to establish HBF as a de facto standard in the rapidly evolving AI memory market. The two companies expect the new technology to gain ground quickly among early adopters, which is an interesting proposition given the dire state of the semiconductor industry.