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  1. Home
  2. Hard Drives
  3. SATA
  4. 3.5"
  5. 4TB
  6. 5.4K RPM
  7. WD40EFPX
Western Digital

WD WD40EFPX 4TB 5400 RPM SATA NAS HDD

MPN: WD40EFPX·By: Western Digital

Part #:WD40EFPXNewIn stock

Ships from the US.

$358.00$89.50 per TB
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WD WD40EFPX 4TB 5400 RPM SATA NAS HDD-
$358.00

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Product overview

The Western Digital WD Red Plus 4TB NAS HDD (model WD40EFPX) is a 3.5-inch SATA 6Gb/s internal hard drive designed for small to medium business (SMB) NAS systems. It features 5400 RPM rotational speed, up to 175 MB/s read speed, and a cache size of 128 MB or 256 MB, enabling reliable performance in RAID-optimized environments with up to 8 bays. NASware 3.0 technology optimizes compatibility and sustained operation, supporting a 180 TB/year workload rate. With 4TB capacity, it handles increased data storage needs for power users and SMBs, including expanded OS support and ZFS. Physical dimensions are 5.79 x 4 x 1.03 inches, weighing 600 grams. Ideal for 24x7 NAS workloads, it uses CMR technology for consistent data integrity in multi-bay setups. Procurement teams benefit from its power efficiency and reliability in home offices, consumer NAS, and commercial applications requiring robust data protection and sharing.

  • 4TB capacity, NASware 3.0 for 8-bay RAID NAS
  • 5400 RPM, 175 MB/s read, 128-256 MB cache
  • SATA 6 Gb/s interface, 180 TB/year workload
  • CMR tech for SMB 24x7 reliability, 1M MTBF
  • 3.5-inch form factor, power-efficient design
  • ZFS/OS compatible for versatile NAS deployment
  • Expedited and overnight shipping options are available at checkout, priced by destination and service.
  • Purchase orders accepted from qualified institutions.
  • Refunds within 14 days and replacements within 30 days of delivery with an RMA (25% restocking fee on customer-initiated returns), and every part carries our Standard 30-Day Warranty - see our return policy or contact US IT Hardware.

Featuring

Manufacturer part #WD40EFPX
BrandWestern Digital
ConditionNew
ModelWD40EFPX
Capacity4 TB
HeatsinkNo
Idle PowerNot found in search results
TechnologyNASware 3.0
Product LineWD Red Plus
Product TypeNAS Internal Hard Drive HDD
Workload Rateup to 180 TB/year
Read/Write PowerNot found in search results
Rotational Speed5400 RPM
NAS CompatibilityUp to 8 bays; RAID-optimized NAS systems

Physical Characteristics

Form Factor3.5-inch

Reliability

Mean Time Between Failures (MTBF)Not found in search results

Interface/Ports

Interface TypeSATA 6 Gb/s; SATA III; ATA-600

Drive Performance

Read Speedup to 175 MB/s
Average Seek TimeNot found in search results
Data Transfer Rate175 MB/s

Weight & Dimensions

Weight600 grams
Cache Size128 MB or 256 MB
Dimensions5.79 x 4 x 1.03 inches (L x W x H)

Environmental Condition

Operating Temperature RangeNot found in search results
Non-Operating Temperature RangeNot found in search results

Compatible systems

Optimized for NAS systems with up to 8 bays; no specific OS or server models listed

  • Generic NAS Systems
    Model: Up to 8-bay
    Form factor: 3.5-inch

    RAID-optimized NAS for small/medium business and SOHO

Best for

  • SMB NAS Systems

    Optimized for small to medium business NAS with up to 8 bays and RAID support, delivering 180 TB/year workload and NASware 3.0 for reliable 24x7 operation.

  • RAID-Optimized Storage

    CMR technology ensures data integrity in multi-bay RAID setups, with 5400 RPM and up to 175 MB/s speeds for consistent performance.

  • Power User NAS

    Handles increased workloads in home offices or power user environments, supporting ZFS and expanded OS compatibility with 4TB capacity.

  • Commercial Data Sharing

    Provides power-efficient storage for sharing growing data volumes in consumer/commercial NAS, rated for 1M hours MTBF.

Frequently asked questions

What is the rotational speed of the WD Red Plus WD40EFPX?

The drive operates at 5400 RPM, balancing performance, power efficiency, and reliability for NAS environments. This speed supports up to 175 MB/s read speeds and is optimized for 24x7 operation in up to 8-bay RAID systems with 180 TB/year workload capacity.

What interface does this NAS HDD use?

It features SATA 6 Gb/s (SATA III, ATA-600) interface for high-speed connectivity in standard NAS enclosures. This ensures compatibility with most SMB NAS systems, delivering transfer rates up to 175 MB/s alongside 128-256 MB cache.

How many NAS bays is it compatible with?

Designed for RAID-optimized NAS systems with up to 8 bays, using NASware 3.0 and CMR technology. Ideal for small to medium businesses handling increased workloads, with support for ZFS and expanded OS compatibility.

What is the workload rating?

Rated for up to 180 TB/year, making it suitable for power users and SMB NAS in 24x7 environments. Combined with 1M hours MTBF, it ensures data integrity and longevity in multi-bay setups.

What are the physical dimensions and weight?

Measures 5.79 x 4 x 1.03 inches (L x W x H) in a 3.5-inch form factor, weighing 600 grams. Fits standard NAS chassis while maintaining power efficiency for rack-mounted or tower deployments.

What cache size does it have?

Cache size is 128 MB or 256 MB, enhancing read/write performance up to 175 MB/s. This improves data access in frequent NAS operations, paired with 5400 RPM for reliable SMB use.

Details

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$358.00$89.50 per TB
Qty
WD WD40EFPX 4TB 5400 RPM SATA NAS HDD-
$358.00
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