HGST HUA722020ALA331

HGST HUA722020ALA331 3.5″ hard drive with a storage capacity of 2 TB and featuring a SATA interface. HGST HUA722020ALA331 Ultrastar A7K2000 2 TB 3.5″ Internal Hard Drive Serial ATA-300 7200 RPM 32 MB Buffer.

All information about the HGST HUA722020ALA331 hard disk drive: technical parameters, failure symptoms, frequently asked questions, reviews, HDD repair and data recovery.

HGST HUA722020ALA331 Technical Details:

Manufacturer:

HGST (Hitachi Global Storage Technologies)

Hard Disk Model:

HUA722020ALA331

Disk Family:

Ultrastar A7K2000

Form Factor:

3.5″

Capacity:

2 TB (2,000,000,000,000 bytes)

Formatted Capacity:

Approximately 1.81 TB

Number Of Disks:

Number Of Heads:

Rotational Speed:

7200 RPM

Average Seek Time:

8.2 ms (read) / 9.2 ms (write)

Disk Interface:

Serial ATA-300 (SATA 3 Gb/s)

Buffer Size:

32768 KB (32 MB)

External Transfer Rate:

300 MB/s

Mean Time Between Failures (MTBF):

1,200,000 hours

Note: The HGST HUA722020ALA331 is part of the Ultrastar A7K2000 series, a high-performance enterprise hard drive line. The A7K2000 series offered capacities up to 2 TB with 7200 RPM spindle speed, designed for demanding enterprise applications and RAID environments.

HGST HUA722020ALA331 Hard Drives:

HUA722020ALA331 – 2 TB SATA 3.5″ Enterprise Hard Drive, Ultrastar A7K2000 series
Model code breakdown: HUA72 (Ultrastar A7K2000) + 2020 (2 TB capacity) + ALA331 (specific variant)
Common firmware revisions: J384A00, J384A01
Recommended usage: Enterprise servers, RAID arrays, high-performance storage

HGST HUA722020ALA331 Failure Symptoms:

Electrical Failure Symptoms:

Drive is powered, but shows no sign of function;
Clicking sound as the heads search or initialize.

Mechanical Failure Symptoms:

Clicking, grinding sounds;
Drive spins but produces rhythmic clicking – typical of head failure.

Logical Failure Examples:

Accidental deletion, accidental format, file corruption;
File system corruption.

Firmware Failure Symptoms:

Drive powers up but is not recognised;
Drive detected with 0 MB capacity.

Bad Platter Area Symptoms:

Hard disk appears to “hang” or be “sluggish”;
Constant CRC errors.

Complex Failure Model

(A combination of two or more of the above failure types)

HGST HUA722020ALA331 Data Recovery & HDD Repair:

This drive has a separate ROM/NVRAM chip on the PCB. When replacing a faulty PCB, you MUST transfer the original ROM chip.

PCB Replacement Information:

To replace a faulty PCB, match the following:

Model number: HUA722020ALA331
PCB part number: Common numbers include 0A32872, 0A32873
Firmware revision: e.g., J384A00, J384A01

⚠️ Critical Note: You MUST transfer the original ROM chip from the old PCB to the new donor board.

Common Failure Scenarios:

Symptom

Likely Cause

Recommended Action

Drive dead (no spin)

PCB failure

Replace PCB; transfer ROM chip

Rhythmic clicking

Head failure

Cleanroom head swap required

Repair Options by Failure Type:

Failure Type

Solution

Requirements

Burnt PCB

Replace PCB; transfer ROM chip

Donor board + soldering

Head failure (clicking)

Head/platter swap

Cleanroom + donor drive

Frequently Asked Questions (FAQs):

Q: What is the capacity?
A: 2 TB (approximately 1.81 TB formatted).

Q: What is the RPM and cache?
A: 7200 RPM and 32 MB cache.

Q: My drive clicks. What’s wrong?
A: Clicking indicates head failure. Seek professional data recovery.

User Reviews & Summary:

Final Verdict:
The HGST HUA722020ALA331 is a reliable enterprise SATA drive suitable for legacy server and RAID applications.