Seagate IronWolf 4TB NAS hard drive review

The IronWolf 4TB is a NAS hard drive rated for 1-8 bays. Seagate sells it as two model numbers, the ST4000VN006 and the ST4000VN008, and several specs differ between them. The ST4000VN006 spins at 5,400rpm with 256MB of cache. The ST4000VN008 spins at 5,900rpm with 64MB of cache. Capacity, CMR recording, the 1M-hour MTBF and the 180TB/year workload rating are the same on both.

Check the model number before you buy. The speed, cache and noise figures below depend on it.

Seagate states that all IronWolf drives use Conventional Magnetic Recording (CMR). Both model numbers use it, so recording type is not a point of difference between them.

The drive is rated for 1,000,000 hours MTBF and 180TB a year of workload. The 1-8 bay rating means Seagate lists it for NAS enclosures from a single bay up to eight. The 180TB/year figure is the number to check against your own traffic if you run frequent backups or a busy media library.

Owner reports are mostly positive on how it behaves in a NAS, with several buyers saying it works well. There is a counterpoint. Three independent complaints describe dead or faulty units. The research does not say how common that is across all sales, but it is a reason to check a new drive fully before putting data on it, and to keep your backups current.

The warranty is three years limited. Seagate also lists Rescue data recovery at three years. A footnote says rescue services are not available in all countries, so confirm it covers you before counting on it.

Owners praise both the warranty and the Rescue recovery service. That makes the cover a genuine part of the appeal. The stated term is three years, and the research lists nothing longer.

Maximum sustained transfer rate is 202MB/s on the ST4000VN006 and 180MB/s on the ST4000VN008. Seagate's figures go no higher than that. The 5,400rpm model with the larger 256MB cache has the higher rated rate, and the 5,900rpm model with 64MB of cache has the lower one.

With sustained rates of 180-202MB/s, this is a drive for capacity, backups and media storage rather than one chosen for peak throughput. The gap between the two models is 22MB/s on paper.

Idle acoustics are 23 dBA on both models. Seek noise is 27 dBA on the ST4000VN006 and 25 dBA on the ST4000VN008. Those are the datasheet figures to weigh if the NAS sits in a home or office.

Owner reports are less settled. Noise feedback is mixed, and it relates to the 5,400rpm model. Since that model has the higher rated seek noise of the two, the reports and the datasheet point the same way. If your NAS lives in a bedroom or a quiet study, factor that in.

Average operating power is 4.8W on both models. Idle power is 3.96W on the ST4000VN006 and 3.95W on the ST4000VN008. Multiply those figures by the number of bays you plan to fill to see the drives' share of your NAS power draw.

One buyer reported a price rise, and one mentioned oversized packaging on a multipack. Each is a single mention, so neither points to a pattern.

The IronWolf 4TB suits a small home or office NAS where CMR, a 3-year warranty and recovery cover matter, and where the listed idle noise and power figures are acceptable. The 1-8 bay rating and 180TB/year workload fit that kind of setup. It suits less well if you need the fastest possible sustained speeds, since Seagate lists 202MB/s at best, or if you cannot tolerate the risk of an early failure, given the three reports of faulty units.