Memory War Z: Samsung spins antidote to 3D XPoint

The 2016 edition of the Flash Memory Summit produced more than the usual amount of excitement. Samsung’s response to the Intel/Micron 3D XPoint challenge arrived in new slideware, indicating the war for next-generation SSDs is just starting. Who has the advantage?

We’d all like to think this is about creating a breakthrough technology, leapfrogging the competition and blowing their roadmap away. On the surface, 3D XPoint does that – in fact, in their launch presentation, the suggestion was made that it has been nearly 30 years since a mainstream memory technology was created, MRAM notwithstanding.

Simple math says Intel and Micron are 4 years ahead, based on 3D XPoint work beginning in 2012. Micron is feverishly evaluating 3D XPoint-based SSDs using sample chips and an FPGA controller, supporting rapid iterations as improved chips drop from the fab. They claim 90% reuse in the controller and firmware, but it would seem this is a classic case of the last 10% of the content being 90% of the effort. 3D XPoint behavior is still a moving target, especially in large SSD configurations.

Samsung has taken the Brad Pitt maneuver from World War Z, calmly watching a zombie mob run down the hallway after 3D XPoint while evaluating its survival options. If there is one concept Samsung understands, it is the winner in non-volatile memory is not the “best” technology. What propelled Samsung to the top in both DRAM and NAND flash was a fab strategy that allowed capacity to be interchanged, creating rapid response to demand swings and shipping product in the face of industry-wide allocation. Good product, solid yield, best availability and pricing.

Meanwhile, Intel is taking its usual brute-force approach. Create a technology so complex that only you and your licensees can build it in silicon. Plow billions of dollars into unique fabs and ruthlessly pursue yield and learning curve reductions. Market the daylights out of the new technology so consumers ask for it – that’s coming next, we’ll see commercials for Intel Optane very shortly.

Here comes Samsung Z-NAND. A quote from the press release:

Samsung has also developed a high performance, ultra-low latency SSD solution, the Z-SSD. Samsung’s Z-SSD shares the fundamental structure of V-NAND and has a unique circuit design and controller that can maximize performance, with four times faster latency and 1.6 times better sequential reading …

In the fine print: this is all from an emulator. It appears from various reports that Samsung has been tinkering with phase-change, if only to debunk some of the 3D XPoint story, and they claim to have comparison data between existing V-NAND SSDs, a (virtual?) prototype of a PRAM-based SSD, and the definitely virtual prototype of a Z-NAND-based SSD.

If Samsung can indeed leverage existing V-NAND technology with increased parallelism – likely through adding planes, similar to 64 regions in 3D XPoint – and build something that looks more like SLC NAND in this new Z-NAND, they can saw years off the fab timeline and have big-time capacity ready to go before 3D XPoint hits volumes.

Bottom line here: Intel has to win, somehow, with its huge investment in 3D XPoint, if not in SSDs then as a DRAM-replacement. Samsung is bound and determined to stay at the top of the pack in SSDs, and will use its capacity story to do that with Z-NAND. It’s all marketing and darned few public technical details right this second; we won’t know how this plays until 2017 at the earliest.