Earlier this year, Western Digital launched its Ultrastar DC SN861 SSDs, but kept quiet about the controller powering these high-performance drives. Naturally, many assumed WD had opted for one of its own controllers. However, a recent teardown reveals a different story: Western Digital has teamed up with Fadu, a South Korean company established in 2015 that focuses on cutting-edge enterprise SSD solutions.
The Ultrastar DC SN861 is tailored for data-centric environments that crave speed, particularly those transitioning to PCIe Gen5 storage. A recent expose by Storage Review highlights its core — Fadu’s FC5161 NVMe 2.0-compliant controller. This powerhouse of a controller includes 16 NAND channels with a 2400 MT/s ONFi 5.0 interface and a host of enterprise-level features. From compliance with OCP Cloud Spec 2.0 and supporting up to 512 namespaces for ZNS to advanced security and energy-saving capabilities, this controller packs a punch unmatched by earlier Western Digital designs.
Performance is where the Ultrastar DC SN861 truly shines. Clocking sequential read speeds reaching 13.7 GB/s and write speeds up to 7.5 GB/s is impressive. When it comes to dealing with random tasks, it hits up to 3.3 million 4K read IOPS and up to 0.8 million 4K write IOPS. The drive offers capacities ranging from 1.6 TB to 7.68 TB, accompanied by endurance ratings of one or three drive writes per day over a span of five years. Additionally, it is available in both U.2 and E1.S form factors.
Interestingly, despite having similar technical specs, each form factor targets different needs. The E1.S version excels in cloud-based environments by incorporating FDP and performance tweaks specific to such use cases. Meanwhile, the U.2 model is optimized for demanding enterprise workloads, including cutting-edge applications like AI developments.
The Ultrastar DC SN861 isn’t only about high performance; it also scores points in power efficiency. With a 5W idle power draw, it’s notably more efficient than previous models like the SN840. While a 1W reduction might seem minor, it can make a significant difference in large-scale deployments where every watt influences total cost of ownership.
Currently, Western Digital is offering these advanced SSDs to select partners, including names like Meta, and other interested buyers. Pricing details remain under wraps, but they will likely vary according to order volumes and specific agreements.
Sources: Fadu, Storage Review
