Western Digital
WD Red Pro 4TB NAS Hard Disk Drive - 7200 RPM SATA 6 Gb/s 64MB Cache 3.5 Inch - WD4001FFSX
Bottom line: The Western Digital WD Red Pro 4TB NAS Hard Disk Drive: 7200 RPM SATA 6 Gb/s with 64MB cache for multi-bay NAS throughput; main trade-off: bare drive only: no screws, SATA cables, or manuals in the box.
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Pros & Cons
Pros
- ✓ 7200 RPM SATA 6 Gb/s with 64MB cache for multi-bay NAS throughput
- ✓ NASware 3.2 firmware adds error recovery control for RAID rebuilds
- ✓ 3D Active Balance Plus cuts vibration in dense 8-16 bay chassis
- ✓ 5-year manufacturer limited warranty, longer than typical desktop drives
- ✓ Rated for 24x7 duty and vetted on WD's NAS compatibility list
Cons
- ✗ Bare drive only: no screws, SATA cables, or manuals in the box
- ✗ 4TB in a 7200 RPM 3.5-inch form factor is low density per bay today
- ✗ 64MB cache trails the 256MB buffers on newer NAS drive families
- ✗ Tuned for 8-16 bay systems, so it is overkill for a 2-bay home NAS
Manufacturer description
WD Red Pro is designed specifically for medium to large NAS systems that have 8 to 16 drive bays. The drives are designed and extensively tested for compatibility in the unique 24x7 operating environment and for the demanding system requirements of medium to large NAS.
SpecPicks Verdict
SpecPicks scored Western Digital WD Red Pro 4TB NAS Hard Disk Drive using a rating × review-volume × price-fit model applied to published specs and reviews across the external storage category. Western Digital's external storage lineup sits within the broader category mid-tier; price and specs are the deciding factors over brand loyalty here. Judge it on the specification table and the price rather than on sentiment: check the figures that decide your use case, then put it side-by-side with two or three close alternatives in the Compare tool before clicking through.
Common buyer scenarios for external storage of this kind: matching it to an existing build, replacing a failing part, or upgrading from a previous-generation equivalent. Check the spec table below against your current setup — particularly socket / form-factor / power-rating fields — and confirm compatibility on the retailer's listing before purchase. Prices and stock are set by the retailer and may have moved since this page was last updated.
Key Features
- Enhanced reliability with 3D Active Balance Plus and error recovery prevention with NASware 3.2
- Extended drive testing to ensure each drive for extended reliable operation
- Most extensive NAS partner compatibility-testing list available
- 5-year manufacturer limited warranty
- Package includes a hard drive only - no screws, cables, manuals included. Please purchase mounting hardware and cables separately if necessary.
Full Specifications
| Brand | Western Digital |
|---|---|
| Color | Red |
| Model Name | Red Pro |
| Read Speed | 540 megabytes_per_second |
| Unit Count | 1 Count |
| Form Factor | 3.5-inch |
| Media Speed | 540 megabytes_per_second |
| Model Number | WD4001FFSX |
| Built-In Media | Hard Drive only |
| Hard-Drive Size | 4 TB |
| Mfr Part Number | WD4001FFSX |
| Number of Items | 1 |
| Special Feature | 3D Active Balance Plus, Advanced Format technology, NAS compatible, NASware technology, Native Command Queuing (NCQ) |
| Item Part Number | WD4001FFSX |
| Hardware Platform | PC; Mac |
| Installation Type | Screw In |
| Compatible Devices | Desktop |
| Data Transfer Rate | 600 megabytes_per_second |
| Enclosure Material | Aluminum |
| Additional Features | 3D Active Balance Plus, Advanced Format technology, NAS compatible, NASware technology, Native Command Queuing (NCQ) |
Ready to buy?
WD Red Pro 4TB NAS Hard Disk Drive - 7200 RPM SATA 6 Gb/s 64MB Cache 3.5 Inch - WD4001FFSX is listed on Amazon. Price, availability, shipping and returns are set by Amazon and its sellers — check the listing for current terms. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.
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