WD WD40EFRX Red 4TB SATA Hard Drive for NAS w/ IntelliPower 6Gb/s 64MB Cache

Western Digital Red Hard Drive Front View
Western Digital Red Hard Drive Front View
Western Digital Red Hard Drive Internal View
Western Digital Red Hard Drive Internal View
Brand : WD
Mfr# : WD40EFRX
Quick : 15915
£116.14 ex vat
Capacity :
Hard Drive Series :

Storage for 1 to 8 bay NAS solutions


The 4TB WD WD40EFRX Red NAS hard drive is designed and tested for compatibility in the unique 24x7 operating environment and demanding system requirements of home and small office Network Attached Storage (NAS). Built in NASware optimises power use resulting in significant power savings and lower hard drive operating temperatures. This improves the overall reliability and performance of the drive and reduces the NAS cost of ownership.

Vital Statistics

  • Model Number: WD40EFRX
  • Capacity: 4TB
  • Speed: IntelliPower
  • Cache: 64MB
  • Interface: SATA 6Gb/s
  • Form factor: 3.5 inch

WD's exclusive NASware technology

WD's exclusive NASware technology, built into every WD WD40EFRX Red hard drive, improves NAS storage performance by reducing common hard drive concerns in NAS systems including concerns for things like compatibility, integration, upgradeability, reliability and cost of ownership that are experienced with a hard drive designed for desktop computers.

Desktop hard drives are designed for desktop computers

Desktop hard drive are designed for optimum performance and reliability in a desktop personal computer. Although they are an affordable alternative to enterprise-class drives, desktop drives have a higher level of risk for potential data loss and failure in an always-on RAID configured NAS system. Specific issues that you may experience using desktop drives in a NAS or RAID environment include:

  • Compatibility: Desktop hard drives are not always tested for compatibility in NAS and can present problems during integration.
  • Reliability: Most desktop drives are not designed for the high operating temperatures or for 24x7 operating environments making them less reliable when used in a NAS system.
  • Error recovery controls: Desktop drives are not traditionally designed for RAID environments and have controls that prevent the RAID controller from assisting in the event of an error which can cause the hard drive to drop off the RAID after a period of time. Rebuilding a RAID often requires several hours and can have a significant impact on downtime and productivity.
  • Noise and vibration: Typically designed for single drive applications, average desktop drives are not optimized for multi-drive systems which have higher noise and vibration levels. When these drives are added to a NAS, the additional vibration can reduce the reliability and life span of the drive.

Enhanced reliability

Your NAS systems is always on, a highly reliable drive is essential. With a 35% MTBF improvement over standard desktop drives, this WD WD40EFRX Red drive is designed and manufactured to be a more reliable and robust solution.

Energy efficient

Reduce your electricity bill and carbon footprint with the WD WD40EFRX Red drives. Innovative technology reduces power consumption and lowers the operating temperature, resulting in a more reliable and affordable solution for always on 24x7 NAS environments.

The WD WD40EFRX Red NAS Hard Drive holds:

  • Up to 800,000 digital photos
  • Up to 1,000,500 songs (MP3)
  • Up to 620,000 songs (uncompressed CD quality)
  • Up to 48 hours of Digital Video (DV)
  • Up to 280 hours of DVD quality video
  • Up to 24 hours of HD video

(Examples of the number of photos, songs, videos and any other files that can be stored on a hard drive are provided for illustrative purposes only. Your results will vary based on file size and format, settings, features, software and other factors.) One gigabyte (GB) = one billion bytes. One terabyte (TB) = one trillion bytes. Total accessible capacity varies depending on operating environment.

Standard Warranty: 3-Years

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