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WD40E31X 14

WD Blue (WD40E31X) 4TB PC SSHD Review

  1. Introduction
  2. Test Setup and Methodology
  3. AS SSD and ATTO Benchmark
  4. ATTO Benchmark
  5. Futuremark Benchmark
  6. AIDA64 Disk Access Test
  7. Sequential Data Performance Test
  8. Random Data Performance Test
  9. Transfer Tests
  10. Conclusion
  11. Online Purchase Links
  12. View All

Disclosure: This review unit is supplied by WD

WD phased out its Green series drives. But at the same time, WD Blue series now has a desktop SSHD drive lineup. This is the WD4031X Blue drive with 4TB drive storage capacity. This drive uses 8GB MLC NAND and a 64MB Cache.

WD40E31X 14

As per WD, this drive uses a set of algorithms which tracks data usage and prioritizes part of the data which is frequently used using the 8GB NAND. One of such uses (as WD highlighted) is for gaming. With this algorithm and the 8GB NAND, it would provide lesser loading times compared to traditional hard drives. With a much larger capacity and value still towards mechanical drives (for now), gamers can keep a large amount of games stored away in the drive.

Fair enough.

SSHD concept isn’t something new. Both Seagate and WD have released its own variants in 2.5” and 3.5” form factors.

  • Specifications 4 TB
    Hard Drive Type WD Blue SSHD
    Model Number WD40E31X
    Interface SATA 6 GB/s
    Formatted Capacity 4 TB
    Form Factor 3.5-inch
    Advanced Format (AF) Yes
    ROHS Compliant Yes
    Data transfer rate (max)
    Buffer to host 6 GB/s
    Host to/from drive (sustained) 150 MB/s
    NAND Type MLC
    NAND Size (GB) 8
    Cache (MB) 64
    Reliability/Data Integrity
    Load/unload cycles 300,000
    Non-recoverable read errors per bits read <1 in 10¹⁴
    Limited warranty (years) 3
    Power Management
    Spinup (Max) 12VDC ±10% (A, peak) 2.8
    Spinup (Max) 5VDC ±10% (A, peak) 1
    Spinup (Max) (W) 38.6
    Average power requirements (W)
    Read/Write 6
    Idle 4.75
    Standby and Sleep 0.57
    Environmental Specifications
    Non-operating 0 to 60
    Shock (Gs) -40 to 70
    Operating (2 ms, read/write) 30
    Non-operating (2 ms) 350
    Acoustics (dBA)
    Idle 25
    Seek (average) 26
    Physical Dimensions
    Height (in./mm, max) 1.028/25.4
    Length (in./mm, max) 5.787/147
    Width (in./mm, ± .01 in.) 4/101.6
    Weight (lb./kg, ± 10%) 0.99/0.45
  • WD40E31X CDI
  • WD40E31X HDD Properties

This is a 5400RPM drive and you get a usable space of 3.63TB. The operating temperature ratings is up to 60 degrees Celsius. This is good considering it can be used in mini-ITX systems even with restricted airflow and even in gaming consoles that have 3.5” bay internally- like the PlayStation 4.

There’s a thin foam between the drive and the PCB to dampen any vibration in between when in use. There’s a small thermal pad on one of the chips on the PCB.

The system that I am using is to test most of the hardware. The same operating system, choice of SATA III port (SATA_1), version of the benchmark software and the testing method is maintained throughout the graph.

Operating System Windows 10 64-bit Pro
Processor+ Cooler Intel i7 4790k + Noctua NH-U12S
Motherboard Gigabyte Z97X-Gaming GT
RAM 8GB Kingston DDR3 HyperX
Primary Storage 240GB SanDisk Extreme II SSD
Secondary Storage 3TB WD Red WD30EFRX
Power Supply Corsair TX750
PC Case Lian Li A70F

The testing methods are as follows:

AS SSD and ATTO Benchmark

Futuremark Storage Benchmarks: PCMark 7 and PCMark 8

AIDA64 Average Read/Write Access Tests: 64KB Block Size

Sequential Data Performance Test (4K Aligned and 512 KiB)

Random Data Performance Test (4k Aligned and 256 KiB)

Transfer Test

My test bench and testing method has changed. For those who need a reference, you can check out the last PC HDD review done on the older test setup.

AS SSD Benchmark

Test the sequential or random read/write performance without using the cache. AS SSD Benchmark reads/writes a 1 GByte file as well as randomly chosen 4K blocks. Additionally, it performs the tests using 1 or 64 threads and it determines the SSD’s access time.

Two extra benchmark tests examine the drive’s behaviour when (1) copying a few big files, a lot of small files and a mixture of file sizes by using cached copy functions of your OS as well as (2) reading/writing data depending on the data’s compressibility.

as ssd

as ssd iops

ATTO Benchmark

The ATTO Disk Benchmark performance measurement tool is compatible with Microsoft Windows. Use ATTO Disk Benchmark to test any manufacturers RAID controllers, storage controllers, host bus adapters (HBAs), hard drives and SSD drives and notice that ATTO products will consistently provide the highest level of performance to your storage.


PCMark 7 Storage Test

The Storage test is a collection of workloads that isolate the performance of your PC’s HDD or SSD. You can choose to test other storage devices in addition to the main system drive.

PCM7 Storage

PCMark 8 Storage Test

Use the PCMark 8 Storage benchmark to test the performance of SSDs, HDDs and hybrid drives with traces recorded from Adobe Creative Suite, Microsoft Office and a selection of popular games. You can test the system drive or any other recognised storage device, including local external drives. Unlike synthetic storage tests, the PCMark 8 Storage benchmark highlights real-world performance differences between storage devices.

PCM8 Storage

Read Test- Total I/Ops

Read Test- Average I/O Response Time

Write Test- Total I/Ops

Response Time- Average I/O Response Time

Read Test- Total I/O

Response Time- Average I/O Response Time

Write Test

Response Time

This drive isn’t just going to be something that gamers will be interested, it’s also those who generate a lot of content, but SSD would be an expensive affair, especially with a much larger storage space.

Mechanical drives are still going to be around, and going Hybrid is the best way to do that while providing an excellent value for the time being. The drive also excels with downloading data from another drive, making it a good choice as a secondary device too. It’s not going to be a replacement for SSDs, just like with any Hybrid mechanical drives tested till now. There are also the choices of Cache SSDs, but it’s not something any of the SSD brands pushed since SanDisk ReadyCache. At the end of the day, this drive is a much better choice for a cost effective large desktop storage and having a NAND seem to have helped in just that.

But eventually, WD will have to consider having a much larger  NAND, especially with a large storage  drive where people who prefer  to use a part of it as a primary partition will multi-task.

WD Blue (WD40E31X) 4TB PC SSHD

  • Hybrid Drive
  • Cost Effective
  • Three-Year Warranty
  • Good enough large file transfer speed- compressed and non-compressed
  • Suitable for those who want a bit better response time with larger storage
  • 8GB NAND isn’t something large in this day of age

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WD Blue SSHD 4TB Desktop SATA 6Gb

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