ST91000640SS Seagate Constellation.2 1TB SAS 64 MB 2.5" Server HDD

High-Performance 2.5-inch Enterprise SAS HDD featuring CMR reliability with the ST91000640SS

The ST91000640SS is a 2.5-inch enterprise HDD designed for SAS server backplanes where predictable latency and continuous operation matter more than peak burst throughput. In CPU-dense rack platforms running modern virtualization stacks, the ST91000640SS provides a stable storage layer for boot/OS volumes and smaller data partitions, keeping compute resources focused on application execution rather than storage recovery or drive behavior variability.

Architecturally, the ST91000640SS fits into PCIe-based storage ecosystems by terminating at the SAS HBA or RAID controller layer, enabling scalable drive counts without consuming CPU PCIe lanes for individual devices. Its CMR recording model supports consistent RAID rebuild characteristics, while 7.2K mechanics and onboard cache are tuned for mixed read/write patterns typical of general-purpose datacenter services. The low-power profile supports higher bay density in 2.5-inch hot-swap chassis, aligning with thermal and power budgets in compact nodes.

Why Choose the ST91000640SS?

The ST91000640SS is selected when enterprise IT teams need a balanced density-to-performance ratio for small-capacity arrays and OS tiers, with SAS dual-port infrastructure compatibility and predictable behavior under RAID. Deploying the ST91000640SS across homogeneous drive groups simplifies spares strategy, controller policy tuning, and lifecycle management for scale-out rack footprints.

Seagate designs the Constellation.2 family with an engineering focus on 24x7 duty cycles, controlled acoustics and vibration tolerance in multi-drive enclosures, and sustained reliability aligned to modern data centre operational standards and hot-swap service models.

Key Applications:

• 2.5-inch SAS server bays
• RAID sets in mixed workloads
• Boot and OS volumes
• General-purpose datacenter storage tiers
• Small-capacity hot-swap arrays

At Happyware - Server Hardware you benefit from non-binding offers tailored to your storage architecture, helping you standardize on ST91000640SS deployments with the right controller and bay compatibility, and you can secure an extended warranty up to 6 years to protect long-running infrastructure plans built around the ST91000640SS.