Western Digital Ultrastar DC SN640 1.92TB NVMe U.2 SSD (0TS1928)
The Western Digital Ultrastar DC SN640 (P/N 0TS1928) is a 1.92TB enterprise NVMe SSD in U.2 2.5-inch form factor, running NVMe 1.3 over a PCIe Gen3 x4 host interface. It targets read-intensive and mixed-use data-center workloads — VM datastores, read caches, boot, web/CDN tiers, and database read replicas — where consistent low-latency and end-to-end data integrity matter more than raw write bandwidth.

Technical Identity
The DC SN640 family is Western Digital's second-generation in-house NVMe data-center SSD line (BiCS3 96-layer 3D TLC NAND), positioned between the read-intensive SN640 RI tier and the mixed-use SN640 MU tier. The 1.92TB SKU sits in the most common enterprise capacity point — large enough for VM clusters and database working sets, small enough to deploy densely in 24-bay 2U or 36-bay 4U NVMe chassis. The PCIe Gen3 x4 link delivers ~3.1 GB/s sequential read and sub-100 µs read latency, with hardware power-loss protection (PLP), end-to-end data-path protection (T10 DIF/PI), and TCG Opal 2.0 self-encryption. MTBF is rated at 2 million hours.

Specifications

OEM: Western Digital (Ultrastar / HGST line)
Series: Ultrastar DC SN640
Part Number: 0TS1928
Capacity: 1.92 TB (usable)
Interface: PCIe Gen3 x4, NVMe 1.3
Form Factor: U.2 2.5-inch 7 mm (SFF-8639)
NAND: BiCS3 96-layer 3D TLC
Endurance Class: Read-Intensive / Mixed-Use
Sequential Read: up to ~3,100 MB/s
Sequential Write: up to ~1,800 MB/s
Random Read (4K): up to ~469K IOPS
Random Write (4K): up to ~63K IOPS
Data Protection: Hardware PLP, end-to-end T10 DIF/PI
Security: TCG Opal 2.0, sanitize, crypto-erase
MTBF: 2,000,000 hours
Condition: Refurbished — tested by T.E.S IT-SOLUTIONS


What This Is NOT

Not a SATA or SAS SSD. The SN640 is NVMe-only — it will not enumerate in a SATA or SAS backplane, even though the U.2 connector is physically SFF-8639.
Not an M.2 drive. This is a 2.5-inch U.2 drive. It will not fit an M.2 2280/22110 slot.
Not PCIe Gen4 or Gen5. The controller is Gen3 x4. It will negotiate down to Gen3 in a Gen4/Gen5 host slot — peak bandwidth stays at Gen3.
Not a high-write-endurance (WI) drive. SN640 is RI/MU class. For write-intensive workloads (heavy OLTP, journaling, hot-tier write cache) use a WI-class drive (e.g., SN840 WI).
Not a consumer SSD. Power-loss protection and T10 DIF make it an enterprise part — and it carries enterprise power draw (~9 W active) and a 2.5-inch 7 mm body.


Compatibility
The 0TS1928 plugs into any U.2 NVMe-capable bay or PCIe-to-U.2 adapter. Typical host environments include Dell PowerEdge R640/R740xd/R7525 (with NVMe backplane SKU), HPE ProLiant DL360/DL380 Gen10/Gen10 Plus (NVMe cage), Supermicro 2029U/2124US NVMe chassis, and Lenovo SR630/SR650 (AnyBay backplane). It is also valid in Tri-Mode HBA/RAID controllers exposed in NVMe pass-through mode (e.g., Broadcom 9400-series). Storage-OS support is broad: VMware ESXi 6.7+/7.x/8.x, Windows Server 2016/2019/2022, RHEL/CentOS/Rocky 7/8/9, Ubuntu 18.04+, Proxmox VE, TrueNAS SCALE, and Ceph/vSAN clusters. Hot-swap behavior follows the chassis backplane — confirm the bay is wired for NVMe (not SAS) and the BIOS is set to PCIe bifurcation/NVMe enumeration where applicable.

FAQ
Q: Can the 0TS1928 SN640 be used in a SATA drive bay?
A: No. The SN640 uses the NVMe protocol over PCIe Gen3 x4. It requires a U.2 NVMe-capable drive bay or a PCIe U.2 adapter. It is not compatible with SATA or SAS backplanes.
Q: What is the form factor of the 0TS1928?
A: U.2 2.5-inch 7 mm (SFF-8639 connector). This is the standard enterprise hot-swap NVMe form factor. It is not M.2 and does not plug directly into a PCIe slot without an adapter.
Q: Will it run at PCIe Gen4 speeds in a Gen4 server?
A: No. The SN640 controller is PCIe Gen3 x4. In a Gen4 or Gen5 host slot the link negotiates down to Gen3 x4 — bandwidth is capped at ~3.1 GB/s sequential read regardless of the host generation.
Q: Is the refurbished SN640 safe for production use?
A: The drive is tested by T.E.S IT-SOLUTIONS. Before placing it in production, verify remaining endurance (Percentage Used / Data Units Written) and drive health via NVMe SMART (nvme-cli, smartctl, or vendor tools) to confirm the drive matches your workload's write profile.

Why TES
T.E.S IT-SOLUTIONS is a European data-center hardware specialist supplying enterprise NVMe storage, NVIDIA Mellanox networking, and server platforms to integrators, hyperscalers, and IT operators. Every refurbished drive is functionally tested, SMART-verified, and securely sanitized before shipment. We hold inventory in EU warehouses, ship across the EU and globally, and back our hardware with a written warranty. For volume requirements, mixed configurations, or specific firmware revisions on the SN640 family, contact our team for a direct quote.