HGST HUS726T4TALS204 4TB SAS Ultrastar HDD: Specs and Buying Guide

Search for this drive and you will find it listed under two different brand names, sometimes on the same page. The HUS726T4TALS204 is a 4TB SAS 12Gb/s 7200RPM 3.5-inch Ultrastar nearline drive, and whether it is called HGST or Western Digital depends entirely on who wrote the listing.

Both are correct. Understanding why saves you from ordering the wrong thing when a search returns what look like two different products.

Decoding an Ultrastar part number

Western Digital acquired HGST, which itself had absorbed Hitachi’s storage division, which had earlier acquired IBM’s drive business. Three generations of consolidation are sitting inside these part numbers, and the naming reflects each layer.

Part numbers beginning HUS and HUC are HGST-era enterprise designations that continue in use. HUS typically denotes a 3.5-inch line, HUC a 2.5-inch one. Numbers beginning 0F, 0B and similar are WD-era catalogue numbers for the same or successor products.

Reading HUS726T4TALS204: the family, then 4T for the 4TB capacity, then the interface and generation coding. The practical takeaway is that the full string identifies the drive precisely, while “4TB Ultrastar SAS” does not — there are several drives that description fits, with different firmware and generations.

Order against the complete part number and the brand label on the listing stops mattering.

HUS726T4TALS204 specifications

Why a nearline drive with a SAS interface

Nearline drives are available in both SAS and SATA at identical capacities, and at first glance SATA looks like free money. The differences show up under load rather than on a spec sheet.

Dual-port paths. A SAS drive presents two independent connections. In a system with redundant controllers or an expander backplane, one path failing does not isolate the drive. SATA has a single path, so any break in it takes the drive offline.

Command queuing depth. SAS handles far more outstanding commands concurrently. That matters most during an array rebuild, when every surviving drive is being read continuously while still serving production traffic. On SATA, that combination is where response times visibly degrade.

Error reporting. SAS provides richer health and error telemetry, which means predictive failure warnings arrive with more warning. On a 4TB drive with a long rebuild window, replacing a drive before it fails rather than after is worth real money.

For a single-path backup target with no redundant controller, SATA at the same capacity is a legitimate saving. Behind a controller pair or in a shared storage array, SAS is the correct specification.

IN STOCK · TESTED

HUS726T4TALS204 – HGST Ultrastar 4TB SAS 12Gb/s 7200RPM 3.5in LFF HDD

SKU: HUS726T4TALS204  |  Refurbished & function-tested  |  30-day warranty

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No carrier, and what that means for you

Unlike OEM-branded drives from HPE, Dell, IBM or Lenovo, this drive is supplied as the bare manufacturer part with no server carrier and no vendor firmware coding.

That makes it the right choice for Supermicro builds, white-box servers, NAS units and any chassis using generic trays, and it is typically cheaper than the OEM-branded equivalent of the same mechanism. Storage-dense JBOD enclosures in particular are usually populated with drives exactly like this.

It is the wrong choice where a Smart Array, PERC or ServeRAID controller expects OEM firmware, or where you need the tray supplied with the drive. In those cases order the OEM part number instead — our compatibility guide lists which part numbers apply to which platform.

4TB and the rebuild window

Four terabytes sits in a comfortable middle ground. Rebuild times are meaningfully longer than on a 1TB drive but nowhere near the day-plus window that 12TB and above can require.

The general principle still applies: rebuild time scales with capacity, and throughout a rebuild the array is degraded while every surviving drive works hard. RAID 6 or another double-parity scheme gives you protection against a second failure during that period, and at 4TB the capacity overhead of double parity is easier to justify than it once was.

Holding a spare on the shelf matters for the same reason. A rebuild cannot begin until a replacement drive is physically present, and every hour waiting on delivery is an hour spent exposed.

Ordering

We supply the HUS726T4TALS204 refurbished and function-tested with a 30-day warranty, single spares or in volume for array population. Browse the full Western Digital and HGST range or our complete enterprise hard drives catalogue.

Common questions

Populating a JBOD or a NAS? Tell us how many bays and we will quote for the full set.