Fadu’s FC5161 SSD Controller Debuts in Western Digital’s PCIe Gen5 Enterprise Drives

Earlier this year, Western Digital unveiled their Ultrastar DC SN861 SSD lineup, leaving many curious about the type of controller at its heart. Initially tight-lipped about these details, speculation arose that WD was relying on a proprietary controller. However, a recent teardown has revealed a different story—the SSDs actually use a controller from Fadu, a South Korean enterprise specializing in high-performance SSD solutions, established in 2015.

The Ultrastar DC SN861 is meticulously crafted for high-demand environments like hyperscale data centers and enterprise sectors transitioning to PCIe Gen5 storage solutions. According to a Storage Review article that took a closer look, the SSD leverages Fadu’s FC5161 controller, compliant with NVMe 2.0 standards. This robust controller supports 16 NAND channels through an ONFi 5.0 2400 MT/s interface and is packed with a suite of enterprise-focused features. These include OCP Cloud Spec 2.0, SR-IOV, capabilities for handling up to 512 name spaces, flexible data placement strategies, NVMe-MI 1.2, and more. It also boasts advanced security and telemetry, not to mention power loss protection, setting it apart from any previous Western Digital controllers.

On the performance front, the Ultrastar DC SN861 dazzles with sequential read speeds reaching 13.7 GB/s and sequential writes capping at 7.5 GB/s. Its prowess in random operations is equally impressive, offering up to 3.3 million 4K random read IOPS and up to 0.8 million 4K random write IOPS. Users can opt for models ranging from 1.6 TB to 7.68 TB, with endurance ratings of one or three drive writes per day (DWPD) over five years. The drives are available in compact U.2 and E1.S form factors, catering to different application needs.

These form factors, though technically similar, are designed for different tasks: the E1.S variant includes FDP and is optimized for cloud environments, while the U.2 version targets high-performance enterprise operations, including AI applications.

Undoubtedly, the Ultrastar DC SN861 stands out as a high-performance contender in the enterprise SSD market. It also surprises with its energy efficiency, consuming only 5 watts at idle—a noteworthy reduction of 1 watt compared to its predecessor, the SN840. For hyperscale deployments, where savings add up over thousands of drives, this can significantly affect the total cost of ownership.

Currently, Western Digital’s Ultrastar DC SN861 SSDs are available to select clients like Meta and other interested entities. Pricing details remain under wraps and will likely vary based on purchasing volumes.

(Information sources: Fadu, Storage Review)