ST4000VX016 vs WD40EFAX
Seagate ST4000VX016 (4TB) versus WD WD40EFAX (4TB)
Verdict
For a NAS or any RAID array, the ST4000VX016 is the clear pick - it's a CMR drive, while the WD40EFAX uses SMR recording, which is not recommended for RAID. Only consider the WD40EFAX for single-drive or archival use.
| ST4000VX016 | WD40EFAX | |
|---|---|---|
| Capacity | 4 TB | 4 TB |
| Recording tech | CMR | SMR |
| RAID / NAS safe | Yes | No |
| Class | Surveillance | NAS |
| Spindle speed | 5900 RPM | 5400 RPM |
| Cache | 256 MB | 256 MB |
| Noise (idle) | 26 dB | 23 dB |
| Fill | Air | Air |
| Interface | SATA | SATA |
| Failure rate (AFR) | - | - |
| Price / TB | $35.15 | $52.65 |
Highlighted cells mark the stronger spec for a NAS build. Failure rates from Backblaze Drive Stats where available; $/TB shows once live prices are wired.