Earlier this year, Western Digital rolled out its Ultrastar DC SN861 SSDs, keeping mum on the controller technology powering these new drives. That had folks guessing that WD might have crafted its own controller. However, a recent teardown reveals a different story: they’ve actually opted for a controller from Fadu, a relatively young enterprise-focused company from South Korea established in 2015 and known for its turnkey SSD solutions.
The Western Digital Ultrastar DC SN861 SSD is tailored for data-hungry hyperscale datacenters and enterprise clients beginning their transition to PCIe Gen5 storage solutions. As detailed in a recent Storage Review article, the drive leverages Fadu’s FC5161 NVMe 2.0 controller. This FC5161 controller comes packed with 16 NAND channels featuring an ONFi 5.0 2400 MT/s interface and a suite of advanced enterprise-grade features including OCP Cloud Spec 2.0, SR-IOV, ZNS support with up to 512 namespaces, and advanced power loss protection, providing a level of versatility and security not present in other controllers on the market or in WD’s previous offerings.
Performance-wise, the Ultrastar DC SN861 doesn’t disappoint. It delivers blazing sequential read speeds that hit up to 13.7 GB/s, with write speeds reaching up to 7.5 GB/s. For random access, the drive pulls in up to a whopping 3.3 million random 4K read IOPS and up to 0.8 million random 4K write IOPS. Available in sizes ranging from 1.6 TB to 7.68 TB, the drives come with endurance ratings of one or three drive writes per day (DWPD) over five years and are available in both U.2 and E1.S form factors.
Despite these form factors sharing much of their technical DNA, Western Digital has fine-tuned each for specific tasks: the E1.S variant boasts FDP and performance perks tailored for cloud environments, whereas the U.2 is better suited for high-octane enterprise operations and cutting-edge applications, like AI.
The Ultrastar DC SN861 doesn’t just excel in performance; it’s also energy efficient, boasting a mere 5W power draw while idle. This is noticeable for enterprise-grade SSDs, even if it’s just a 1W drop from the SN840. In large-scale deployments where every watt can shave off costs, that’s a big deal.
Now, these Ultrastar DC SN861 SSDs are available to a select group of customers, including major names like Meta, as well as other interested buyers. Pricing remains under wraps, likely varying according to order quantities and specific needs.
