WD Ultrastar DC SN655 7.68TB U.3 NVMe SSD

The WD Ultrastar DC SN655 7.68TB is an enterprise-grade U.3 NVMe SSD delivering up to 6800 MB/s sequential read and 2000 MB/s sequential write over PCIe Gen4. Built on BiCS5 3D TLC NAND with NVMe 1.4b compliance, it is optimized for read-intensive workloads in cloud data centers and scale-out server environments.

Ideal for cloud service providers, AI and machine learning platforms, big data analytics, NoSQL distributed databases, and software-defined storage environments that demand consistent high throughput and low latency at scale. The SN655 supports both U.2 and U.3 backplanes, making it easy to integrate into existing enterprise storage infrastructure.

Backed by Western Digital's 2.5 million hour projected MTBF and a 5-year limited warranty, the SN655 delivers enterprise-class reliability with 1.0 DWPD endurance rating. It includes enterprise features such as power loss protection, end-to-end data path protection, Instant Secure Erase (ISE), and dual-port redundancy with failover capability.

Key Features of the WD Ultrastar DC SN655 7.68TB

• High Sequential Read: Up to 6800 MB/s sequential read throughput (128 KiB) for fast data retrieval in demanding workloads
• PCIe Gen4 Interface: Next-generation PCIe 4.0 with NVMe 1.4b compliance for low-latency host access
• BiCS5 3D TLC NAND: Western Digital's latest 3D NAND technology enabling high capacities and efficient bit density
• Dual-Port Redundancy: U.3 interface supports dual-port operation with failover capability for high-availability environments
• Enterprise Data Protection: Power loss protection and end-to-end data path protection safeguard data integrity
• Flexible Security Options: Available with Secure Erase (SE), Instant Secure Erase (ISE), or TCG Ruby encryption
• Broad Backplane Compatibility: U.3 interface is backward compatible with U.2 backplanes
• 5-Year Limited Warranty: Enterprise-class reliability backed by Western Digital's warranty and 2.5M hour projected MTBF

Technical Specifications

• Capacity: 7.68 TB
• Form Factor: 2.5 inch U.3, 15 mm
• Interface: PCIe Gen4, NVMe 1.4
• Sequential Read: 6800 MB/s (128 KiB)
• Sequential Write: 2000 MB/s (128 KiB)
• Random Read IOPS: 980K IOPS (4 KiB)
• Random Write IOPS: 80K IOPS (4 KiB)
• Read Latency: 78 microseconds
• Write Latency: 15 microseconds
• Endurance (DWPD): 1.0 DWPD over 5 years
• MTBF: 2.5 million hours (projected)
• UBER: 1 in 10^17
• AFR: 0.35% (projected)
• Power Requirement: +12V DC
• Operating Power: 16W / 20W (default)
• Idle Power: Less than 8W
• Dimensions: 69.85 mm x 100.45 mm x 15 mm
• Operating Temperature: 0 degrees C to 70 degrees C
• Security: SE, ISE, TCG Ruby
• NAND Type: BiCS5 3D TLC NAND
• Controller: Western Digital NVMe 1.4b
• Warranty: 5 Year Limited