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WD

Ultrastar DC HC520 12TB SATA

HUH721212ALE604
Ultrastar DCnearlineCMR12TBSATA-6G3.5"
$19.17/TB
$229.99
REFURBIn Stock
Updated Mar 22, 2026, 01:44 PM
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Quick Verdict

The WD Ultrastar DC HC520 12TB SATA is a 12TB SATA-6G enterprise drive at $19.17/TB - CMR recording makes it safe for all RAID levels and NAS deployments. As a refurbished unit, run SMART diagnostics on arrival and verify power-on hours.

Specifications

Capacity12TB
Form Factor3.5"
InterfaceSATA-6G
Recording TechCMR
RPM7200
Cache256MB
Sector Size512e
Workload Rating550TB/yr
Warranty5 years
ASINB084JC2VG7

90-Day Price History

$18$20$2103/2305/0506/17
How it compares - 12TB SATA-6G
#1MDD 12TB SATA 6G 7200RPM NAS
$19.17/TB
#2WD Ultrastar DC HC520 12TB SATATHIS DRIVE
$19.17/TB
#3MDD 12TB SATA 6G 7200RPM 256MB NAS
$24.17/TB
#4MDD 12TB SATA 6G 7200RPM Enterprise
$24.66/TB
#5Synology HAT5300 12TB NAS
$—/TB

Compare to similar 12TB SATA-6G drives

MDD
12TB SATA 6G 7200RPM NAS
$19.17/TB
$229.99
new
MDD
12TB SATA 6G 7200RPM 256MB NAS
$24.17/TB
$289.99
new
MDD
12TB SATA 6G 7200RPM Enterprise
$24.66/TB
$295.95
new
Synology
HAT5300 12TB NAS
$—/TB
$—
Seagate
IronWolf 12TB NAS
$—/TB
$—

Frequently Asked Questions

Yes. The Ultrastar DC HC520 12TB SATA uses CMR recording which is fully compatible with all RAID levels. It is rated for 550TB/year workload.

5-year manufacturer warranty. This listing is a refurbished/renewed unit - verify seller warranty before purchase.

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 high-capacity NAS for media, backups and file sharing.
✓ Excellent fit
CMR recording is RAID-safe and fully compatible with Synology, QNAP, TrueNAS and UnRAID. Refurb units offer strong value for non-critical NAS.
💾
Backup Server / Veeam Target
Dedicated backup storage for Veeam, Commvault, or NetBackup.
✓ Excellent fit
12TB 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. Critical for refurb drives — refuse any with reallocated sectors > 0.
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 6 hours for 12TB. 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 12TB 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.