Lenovo 4XB7A13556 ST50 3.5 4TB 7.2K Non-hs SATA HDD

Lenovo 4XB7A13556 3.5-Inch 4TB 7200 RPM SATA Hard Drive for ThinkSystem ST50

Overview

The Lenovo 4XB7A13556 is a non-hot-swap 3.5-inch, 4TB SATA hard drive validated for the Lenovo ThinkSystem ST50 server platform. If you're deploying or expanding a ThinkSystem ST50 for on-premises workloads — file storage, backup targets, or light database use — this drive is the factory-matched option that eliminates compatibility guesswork. It ships as a non-hot-swap (NON-HS) unit, which matters for planning: the ST50 must be powered down to swap it, so factor that into your maintenance window strategy before committing to this configuration.

At 4TB and 7200 RPM on a 6 Gbit/s SATA interface, this drive delivers solid sequential throughput for general-purpose server storage without the cost premium of SAS or the endurance trade-offs of consumer-grade drives. It's a straightforward capacity drive — not a performance-first choice, but the right pick when you need verified Lenovo compatibility and a predictable cost-per-terabyte in an ST50 chassis.

Key Features

• 4TB Capacity on SATA 6 Gbit/s: Four terabytes at full 6 Gbit/s interface speed gives you enough headroom for multi-week retention windows on moderate workloads. The SATA interface keeps it compatible with standard HBA configurations — no SAS controller required, which simplifies the ST50's internal wiring and lowers total BOM cost.
• 7200 RPM Spindle Speed: Running at 7,200 RPM rather than a 5,400 RPM nearline speed means noticeably better random-read latency and sustained sequential throughput — relevant if this drive is serving active workloads (VM storage, working-set data) rather than pure cold backup. For a write-heavy archive tier, the RPM advantage narrows, but for mixed-use ST50 deployments it pays off.
• 3.5-Inch Non-Hot-Swap Form Factor: The 3.5-inch NON-HS designation is specific to how this drive seats in the ST50's drive bays. Non-hot-swap means there's no backplane-managed carrier — the drive is inserted directly, and the server must be shut down before removal or replacement. Plan accordingly if uptime SLAs are tight.
• 5V / 12V Dual-Rail Power: The drive draws from both the 5V and 12V rails via a standard SATA power connector, consistent with the ST50's internal power distribution. No adapters or special cabling required — plug it into an available SATA data and power connector and you're done.
• Validated for ThinkSystem ST50: Lenovo's compatibility list explicitly includes the ST50 for this part number. Buying a drive that's been validated against the platform's firmware and controller stack reduces the risk of unexpected behavior — particularly relevant in environments where stability trumps raw cost savings.
• Compact Physical Footprint Despite High Capacity: At 7.50 × 10.00 × 4.00 inches and 2.05 lbs, the drive fits the ST50's standard 3.5-inch bays without modification. The weight is consistent with a full-height 3.5-inch unit — no surprises when it comes to bay loading or vibration management in a single-socket tower chassis.

Integration & Compatibility

The 4XB7A13556 is validated for the Lenovo ThinkSystem ST50, a single-socket entry-level tower server commonly deployed in small branch offices, retail back offices, and light industrial environments. The ST50's non-hot-swap bay configuration is designed around drives like this — you don't need a SAS expander, RAID controller upgrade, or third-party carrier bracket. Pair it with the ST50's onboard SATA controller or an optional RAID adapter for basic redundancy configurations.

If you're building out a multi-drive array in the ST50, keep in mind this is a non-hot-swap chassis — drive changes require a planned outage. For environments that can't tolerate unplanned downtime for drive replacement, evaluate whether a hot-swap-capable platform is a better architectural fit. For scheduled maintenance windows — which is the norm in many SMB and light enterprise deployments — the NON-HS configuration is operationally straightforward.

The SATA 6 Gbit/s interface is backward-compatible with SATA 3 Gbit/s controllers, so if the ST50 is ever paired with an older HBA or repurposed into a different chassis, this drive will function — at the lower interface speed. For network-attached storage or direct-attached storage expansion, this drive also fits standard 3.5-inch NAS bays from most major vendors, though Lenovo validation applies specifically to the ST50.

Frequently Asked Questions

Q: Is the Lenovo 4XB7A13556 compatible with the ThinkSystem ST50?

A: Yes. The 4XB7A13556 is explicitly validated for the Lenovo ThinkSystem ST50. It is designed to seat in the ST50's 3.5-inch non-hot-swap drive bays without modification.

Q: What does NON-HS mean on the 4XB7A13556?

A: NON-HS stands for non-hot-swap. The drive does not use a hot-swap backplane carrier. The server must be powered down before inserting or removing this drive. This is standard for the ST50's entry-level bay configuration.

Q: What interface does the 4XB7A13556 use?

A: The drive uses a SATA interface running at 6 Gbit/s. This is compatible with the ST50's onboard SATA controller and is backward-compatible with SATA 3 Gbit/s connections.

Q: How fast does the 4XB7A13556 spin?

A: The drive spins at 7,200 RPM. This provides better sequential and random-read performance compared to 5,400 RPM nearline drives — relevant for mixed-use server workloads where latency matters.

Q: Can I use the 4XB7A13556 in a NAS or non-Lenovo server?

A: Physically, the 3.5-inch SATA form factor fits most standard NAS and server bays. However, Lenovo's firmware validation applies specifically to the ThinkSystem ST50. Compatibility with other platforms is not guaranteed by this product listing.

Q: What are the power requirements for the 4XB7A13556?

A: The drive operates on standard 5V and 12V dual-rail SATA power — no adapters required. It uses a standard SATA power connector consistent with the ST50's internal power distribution.

Karl Wilson

The 4XB7A13556 is one of those parts that looks simple on paper but has a spec detail that trips up buyers: the NON-HS designation. In the ThinkSystem ST50 chassis, this means no hot-swap backplane — the drive connects directly to the motherboard SATA controller or onboard HBA, and you're committing to a planned-outage maintenance model. If that's acceptable for your deployment, this 4TB 7200 RPM unit is the validated path for expanding ST50 storage capacity without stepping outside Lenovo's compatibility matrix.

Technical Highlights:

• 6 Gbit/s SATA Interface: Full SATA III throughput from the onboard controller — no bottleneck at the interface level for the ST50's workload range. Backward-compatible with SATA 3 Gbit/s if the chassis is ever repurposed.
• 7,200 RPM vs. Nearline 5,400 RPM: The spindle speed advantage is measurable on read-heavy mixed workloads — roughly 20–30% better random-read IOPS compared to a 5,400 RPM drive of comparable capacity. For a file server or light VM host, that matters at queue depth 1–4.
• 2.05 lb / 3.5-Inch Form Factor: Standard full-height 3.5-inch physical spec — fits the ST50's drive bays without brackets or adapters. Weight is within normal range for a loaded 4TB platter unit.

Deployment Considerations:

• The non-hot-swap configuration requires a full server shutdown for drive swap or replacement. If the ST50 is running a workload that cannot tolerate planned downtime windows, evaluate the hot-swap-capable ThinkSystem ST50 configurations or a different platform entirely.
• This drive's Lenovo validation is specific to the ThinkSystem ST50. Using it in third-party server or NAS chassis is physically possible via SATA, but firmware-level validation (drive health reporting, predictive failure alerts via Lenovo XClarity) will not apply.

Best fit: a ThinkSystem ST50 deployed as a branch office file server, backup target, or light application host where maintenance windows are scheduled and the priority is Lenovo-validated storage expansion at a predictable cost-per-terabyte.