WD

Ultrastar 7K4000 4TB SATA NAS

HMS5C4040ALE640
UltrastarnearlineCMR4TBSATA-6G3.5"
$36.25/TB
$145.00
newIn Stock
Updated Jun 17, 2026, 09:31 AM
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Quick Verdict

The WD Ultrastar 7K4000 4TB SATA NAS is a 4TB SATA-6G enterprise drive at $36.25/TB - CMR recording makes it safe for all RAID levels and NAS deployments. New unit with full manufacturer warranty.

Specifications

Capacity4TB
Form Factor3.5"
InterfaceSATA-6G
Recording TechCMR
RPM7200
Cache
Sector Size512n
Workload Rating
Warranty
ASINB00E939BFY

90-Day Price History

$23$31$3903/2305/0806/17
How it compares - 4TB SATA-6G
#1Seagate IronWolf 4TB NAS
$25.00/TB
#2WD Ultrastar 7K4000 4TB SATA NASTHIS DRIVE
$27.00/TB
#3Seagate ST4000NM0033 4TB SATA Enterprise
$28.50/TB
#4Seagate ST4000NM0033 4TB SATA Enterprise
$28.50/TB
#5WD Ultrastar 7K4000 4TB SATA NASTHIS DRIVE
$36.25/TB

Frequently Asked Questions

Yes. The Ultrastar 7K4000 4TB SATA NAS uses CMR recording which is fully compatible with all RAID levels.

Warranty varies by seller. Check the Amazon listing for current warranty terms.

Compatible with any server, NAS or workstation with a SATA port. Works in Synology, QNAP, TrueNAS, UnRAID and all major NAS platforms.

Use Case Scenarios

🏠
Home & SMB NAS
Building a mid-range NAS for media, backups and file sharing.
✓ Excellent fit
CMR recording is RAID-safe and fully compatible with Synology, QNAP, TrueNAS and UnRAID. New drives come with full warranty.
💾
Backup Server / Veeam Target
Dedicated backup storage for Veeam, Commvault, or NetBackup.
✓ Excellent fit
4TB SATA drives are ideal for backup targets. SATA gives maximum $/TB for backup repositories.
🏗️
Virtualization Host Storage
VM images and snapshots on Proxmox, VMware or Hyper-V.
~ Good fit
Suitable for VM storage where workloads are not IOPS-intensive. SATA is fine for single-host VM storage. Consider NVMe cache for latency-sensitive VMs.

Maintenance & Troubleshooting

Maintenance Checklist

On installCheck SMART baseline on arrival
Run smartctl -a /dev/sdX and record: Reallocated_Sector_Ct, Power_On_Hours, Spin_Retry_Count. Establishes baseline for future comparison.
MonthlyRun SMART short self-test
smartctl -t short /dev/sdX — takes 1-2 minutes, catches most developing issues. Schedule during off-peak.
QuarterlyRun SMART long self-test
smartctl -t long /dev/sdX — full surface scan, takes 2 hours for 4TB. Any test failure is grounds for immediate replacement.
QuarterlyCheck RAID array health
Verify no degraded drives. A degraded array with no hot spare is one failure from data loss. Check mdstat or controller UI.
AnnuallyVerify drive firmware version
Check WD support site for firmware updates. Some versions have known bugs affecting integrity.
Every 3-5 yearsPlan proactive replacement
Enterprise HDDs have higher failure rates after year 4-5. At 4TB per drive, budget for replacements before failures occur.

Troubleshooting Guide

Cause: Loose SATA data or power cable, failed port, or drive not spinning up.
Fix: Reseat both cables. Try a different port. Listen for spin-up sound. Test with a known-good cable.