HGST HUS724020ALA640 3.5″ hard drive with a storage capacity of 2 TB and featuring a SATA interface. HGST HUS724020ALA640 Ultrastar 7K4000 2 TB 3.5″ Internal Hard Drive Serial ATA-600 7200 RPM 64 MB Buffer.
All information about the HGST HUS724020ALA640 hard disk drive: technical parameters, failure symptoms, frequently asked questions, reviews, HDD repair and data recovery.
HGST HUS724020ALA640 Technical Details:
Note: The HGST HUS724020ALA640 is part of the Ultrastar 7K4000 series, an enterprise-class 7200 RPM hard drive line. The 7K4000 series was designed for nearline storage, RAID arrays, and data center applications requiring high capacity and reliability. This series features Advanced Format 4K sectors and enhanced error recovery for RAID environments.
HGST HUS724020ALA640 Hard Drives:
- HUS724020ALA640 – 2 TB SATA 3.5″ Enterprise Hard Drive, Ultrastar 7K4000 series
- Model code breakdown: HUS72 (Ultrastar 7K4000) + 4020 (2 TB capacity) + ALA640 (specific variant)
- Common firmware revisions: J384A00, J384A01, J384A02
- Advanced Format: 512e (4K physical sectors)
- Recommended usage: Enterprise nearline storage, RAID arrays, data centers
HGST HUS724020ALA640 Failure Symptoms:
Electrical Failure Symptoms:
- Drive is powered, but shows no sign of function;
- Clicking sound as the heads search or initialize;
- Burnt components on PCB.
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;
- RAID array drive dropout.
Firmware Failure Symptoms:
- Drive powers up but is not recognised;
- Drive detected with 0 MB capacity;
- SMART attributes showing unusual values.
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 HUS724020ALA640 Data Recovery & HDD Repair:
This enterprise 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: HUS724020ALA640
- PCB part number: Common numbers include 0A90020, 0A90021, 0A90720
- Main controller IC: Often 88i9346 (Marvell)
- Firmware revision: e.g., J384A00, J384A01, J384A02
⚠️ Critical Note: You MUST transfer the original ROM chip from the old PCB to the new donor board. Without this, the drive will not function correctly. The Ultrastar 7K4000 series is known for excellent reliability, but firmware corruption can occur.
Common Failure Scenarios:
Repair Options by Failure Type:
Frequently Asked Questions (FAQs):
Q: Is the HUS724020ALA640 a 3.5″ or 2.5″ drive?
A: It is a 3.5-inch enterprise hard drive.
Q: What is the capacity?
A: 2 TB (approximately 1.81 TB formatted).
Q: What is the RPM and cache?
A: 7200 RPM and 64 MB cache.
Q: Is this drive good for NAS?
A: Yes, the Ultrastar 7K4000 series is excellent for NAS and RAID environments.
Q: My drive clicks. What’s wrong?
A: Clicking indicates head failure. Seek professional data recovery.
User Reviews & Summary:
Pros:
– 2 million hour MTBF – excellent enterprise reliability
– 7200 RPM – good performance
– 64 MB cache
– 550 TB/year workload rating
– Designed for 24/7 operation
– Trusted Ultrastar reliability
Cons:
– 2 TB capacity is modest by modern standards
– Discontinued – used only
Final Verdict:
The HGST HUS724020ALA640 (Ultrastar 7K4000, 2 TB) is a reliable enterprise SATA drive suitable for legacy server and RAID applications. For data recovery, professional assistance is recommended for valuable data.