Western Digital WD40EFRX WD Red NAS Hard Drive - Hard drive - 4 TB - internal - 3.5 inch - SATA 6Gb/s - buffer: 64 MB - for WD My Cloud EX2, EX4
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AI Verdict
This 4TB, 3.5-inch SATA 6Gb/s drive with 64MB buffer is for 1-5 bay NAS systems needing 24/7 operation and data integrity over raw speed.
This 4TB WD Red drive is a strong fit for its intended use in 1-5 bay NAS systems, offering 24/7 operation and NASware 2.0 for data integrity. Its CMR technology ensures consistent performance in RAID arrays, which is crucial for network storage. It's not about raw speed, but about sustained, reliable access.
If you need higher capacity or faster transfer rates for more demanding NAS workloads, look for WD Red Plus or Pro models with 7200 RPM and larger caches.
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Pros
- Designed for continuous 24/7 operation in NAS environments.
- Features NASware 2.0 firmware for improved compatibility and error recovery in RAID setups.
- Operates quietly and maintains low temperatures during use.
- Offers 4000 GB capacity in a 3.5-inch form factor, suitable for multi-bay NAS units.
- Utilizes Conventional Magnetic Recording (CMR) technology, preferred for NAS over SMR for consistent performance.
- Backed by a 3-year limited warranty.
Cons
- Internal transfer rates around 150 MB/s are not designed for high-speed desktop applications.
- Some users reported receiving Dead on Arrival (DOA) units.
- The model is older, with some vendors marking it as 'end of life' around 2020.
- White-labeled versions might indicate recertified drives or those shucked from external enclosures, raising legitimacy concerns.
Dimension Scores
Internal transfer rates are around 150 MB/s, with real-world copies at 143 MB/s, which is average for a 5400 RPM NAS drive but not fast for general use.
Designed for 24/7 operation with a 1,000,000 hour MTBF and NASware 2.0 for enhanced data protection and error recovery.
4TB is a common and useful capacity for small to medium NAS setups, offering a balance between cost and storage space for 1-5 bay systems.
Specifically engineered for 1-5 bay NAS systems and compatible with desktop PCs, making it broadly usable within its intended scope.
Best For
- Small home or office 1-5 bay Network Attached Storage (NAS) systems requiring 24/7 uptime.
- Users prioritizing data reliability and integrity in a RAID configuration.
- Media streaming servers that need consistent access to large files without demanding peak transfer speeds.
Not Recommended For
- Desktop PCs where maximum read/write speed is the primary concern for gaming or video editing.
- Users who frequently move the drive or require robust shock protection beyond typical NAS enclosures.
- Budget-conscious buyers looking for the absolute lowest cost per terabyte, as newer SMR drives might be cheaper.
Watch Out For
- Some buyers reported drives arriving dead, requiring immediate return and replacement.
- If you find a white-label version, it might be a recertified drive or from an external enclosure, which could affect warranty or expected lifespan.
- The 4TB capacity might be insufficient for large-scale data hoarders or professional video archives, leading to quicker upgrade cycles.
- Real-world transfer speeds can drop to around 143 MB/s during large file copies, slower than peak benchmark results.
Full Specifications
| ASIN | B01IF6879G |
| Brand | Western Digital |
| Color | Red |
| Series | My Cloud EX2 |
| Hard Drive | 4 TB Raid |
| Item Weight | 0.01 ounces |
| Manufacturer | WESTERN DIGITAL TECH |
| Special Feature | Portable |
| Flash Memory Size | 4 |
| Hardware Platform | PC |
| Installation Type | Internal Hard Drive |
| Item model number | WD40EFRX |
| Compatible Devices | Desktop |
| Product Dimensions | 4.02 x 5.79 x 1.02 inches |
| Hard Disk Interface | SATA 6 GB/s |
| Hard Drive Interface | SATA 6 GB/s |
| Number of Processors | 4 |
| Hard Disk Description | Raid |
| Hard Disk Form Factor | 3.5 Inches |
| Item Dimensions LxWxH | 4.02 x 5.79 x 1.02 inches |
| Connectivity Technology | SATA |
| Digital Storage Capacity | 4000 GB |
| Hard Drive Rotational Speed | 5400 RPM |
| Is Discontinued By Manufacturer | No |
What Buyers Say
The biggest takeaway from users is that this WD Red drive, the WD40EFRX, is a reliable workhorse for NAS, especially because it's a CMR drive, unlike some later Red models that caused headaches. People consistently mention it running quietly and cool, which is a huge plus for a drive that's supposed to be on all the time. While nobody's buying it for blazing speed, it delivers consistent performance for media streaming and backups. The main gripes are occasional DOA units and the fact that it's an older model, so finding new stock might be tricky now.
“Got this 4TB Red for my Synology, and it just works, man. Super quiet, doesn't get hot like my old desktop drives. Had one DOA once, but Amazon swapped it quick. For my Plex server, it's perfect, not fast but never skips a beat.”
Common Praise
- Runs quietly, making it suitable for home environments.
- Operates at low temperatures, contributing to a longer lifespan.
- Reliable for continuous 24/7 operation in NAS systems.
- Easy installation process in NAS enclosures.
- NASware 2.0 firmware effectively manages RAID configurations and power.
- Consistent performance for data storage and media serving.
Common Complaints
- Some units arrived Dead on Arrival (DOA), requiring immediate returns.
- Not the fastest drive, with internal transfer rates around 150 MB/s, slower than some desktop drives.
- The model is considered older, with some vendors marking it as 'end of life'.
- Concerns about 'white label' drives being recertified or from external enclosures, potentially affecting trust.
Ownership Tips
- The 'IntelliPower' feature really does keep it quiet, even when the NAS is under load.
- It doesn't generate much heat, which is a relief in a multi-bay enclosure.
- The 3-year warranty is a comfort, though I haven't had to use it yet.
- Rebuilding a RAID array with these is slower than with 7200 RPM drives, but it finishes without errors.
- The 4TB capacity fills up faster than you'd think if you're storing a lot of 4K video.
Frequently Asked Questions
Is this drive suitable for a desktop computer?
While it can technically be used in a desktop, this drive is optimized for NAS systems with features like NASware 2.0 and 24/7 operation. For a desktop, you might find faster, cheaper options not designed for continuous use.
What does 'IntelliPower' mean for the RPM?
IntelliPower means the drive's rotational speed is not fixed at 5400 RPM but dynamically adjusts to optimize power consumption, noise levels, and performance for its NAS environment.
Is this a CMR or SMR drive?
The WD40EFRX model is a Conventional Magnetic Recording (CMR) drive. This is important for NAS users as CMR generally offers better and more consistent performance, especially during RAID rebuilds, compared to Shingled Magnetic Recording (SMR) drives.
Can I use this drive in a RAID configuration?
Yes, it's designed for RAID environments in NAS systems, featuring NASware 2.0 firmware that includes error recovery controls to make RAID configurations more reliable and reduce errors.
What is the warranty period for this drive?
This WD Red drive comes with a 3-year limited warranty.
Buying Guide
When you're looking at a hard drive like this, especially for a NAS, you're not just buying storage; you're buying reliability for your always-on data. You need to think about how often it'll be running, what kind of data you're putting on it, and if it's going into a RAID. This drive is built for constant operation and data integrity, not for being the fastest thing on the block. Don't just chase the biggest number on the box; consider the 'Red' designation, which means it's tuned for NAS environments.
Capacity (4000 GB)
This is how much data you can store. 4000 GB (4TB) is enough for a decent amount of photos, videos, and documents, but if you're archiving huge media libraries, you might fill it up faster than you expect. Think of it like the size of your digital closet.
Interface (SATA 6Gb/s)
This is the connection speed between the drive and your computer or NAS. 6 Gigabits per second is standard for modern hard drives and won't be a bottleneck for this drive's performance, which is more about consistent access than burst speed.
Form Factor (3.5 Inches)
This refers to the physical size of the drive. 3.5-inch drives are the standard size for desktop computers and most multi-bay NAS enclosures. Make sure your NAS or PC has bays that fit this size.
Drive Type (Raid)
This indicates the drive is optimized for use in RAID arrays, where multiple drives work together for performance or data redundancy. Drives optimized for RAID have specific firmware (like NASware 2.0 here) to handle error recovery and vibration better, which is crucial for data protection in a NAS.
Alternatives
If this drive doesn't offer enough speed, look for drives with 7200 RPM and larger cache sizes. If you need more capacity, search for drives with 6TB, 8TB, or higher capacities, specifically labeled as 'NAS' or 'Pro' versions to ensure CMR technology.
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