Japan

Hitachi

Hitachi's enterprise drives, sold refurbished

The Hitachi drives here

An Ultrastar DC HC310 4 TB, sold renewed on Amazon.com, and two MegaScale DC 4 TB drives listed on the European Amazon stores — one on the internal drive shelf, one, declared refurbished, on the NAS drive shelf.

Enterprise figures on second-hand drives

The Ultrastar publishes the highest workload rating and the highest MTBF on the NAS drive shelf — 550 TB a year and 2 million hours — with CMR, 7200 rpm, 256 MB of cache, a non-volatile cache and 512e sectors. Those figures describe new drives in a fleet; this one is renewed, and its page gives no warranty term at all.

The MegaScale pair

The refurbished MegaScale on the NAS shelf gives 5,700 rpm, 64 MB of cache and 800,000 hours MTBF, with no recording method and no warranty term. The one on the internal shelf prints 7,200 rpm in a title its single bullet repeats word for word. Neither is sold on Amazon.com.

Every Hitachi unit reviewed here

Internal hard drives

Hitachi MegaScale DC 4000.B 4 TB (0F22146)

4 TB · 3.5-inch · 7200 rpm · 64 MB cache · SATA 6 Gb/s · one bullet, which repeats the title · no duty figure of any kind

A four-terabyte drive whose single bullet reprints its title word for word, publishing every mechanical figure and not one figure about what the drive is specified to withstand.

Best for: A bulk volume in a desktop machine where the drive will not be pushed hard, bought by someone comparing on figures alone and getting the rest from the datasheet.

7.2/10

No Amazon.com offer on October 26, 2026

Search Amazon for this model Read the review: Hitachi MegaScale DC 4000.B 4 TB (0F22146)
NAS hard drives

Hitachi MegaScale DC 4 TB, refurbished

4 TB · 5700 rpm · 64 MB cache · SATA 6 Gb/s · 800,000 hours MTBF · refurbished with no operating hours · recording method not published

A refurbished four-terabyte drive that publishes a rotational speed, a cache figure and an MTBF, and that names neither its recording method nor any warranty term.

Best for: A bulk volume in a multi-drive enclosure where the workload is light and steady, bought by someone who has already decided how they will handle a failure.

7.2/10

No Amazon.com offer on October 26, 2026

Search Amazon for this model Read the review: Hitachi MegaScale DC 4 TB, refurbished
NAS hard drives

Hitachi Ultrastar DC HC310 4 TB, renewed

4 TB renewed · CMR · 550 TB a year · 7200 rpm · 256 MB with non-volatile cache · 512e sectors · 2 million hours · no warranty term

A renewed enterprise drive carrying the highest workload rating and the highest MTBF on this shelf, and no warranty term of any kind to stand behind either figure.

Best for: A spare or a cold-storage drive for a buyer who accepts a renewed drive without a stated warranty, once an offer is listed again.

No Amazon.com offer on October 26, 2026

Check price on Amazon Read the review: Hitachi Ultrastar DC HC310 4 TB, renewed

What each Hitachi review concluded

Hitachi MegaScale DC 4000.B 4 TB (0F22146) — A page with no marketing on it at all, which is refreshing until the figures run out.
Hitachi MegaScale DC 4 TB — The mechanical figures are all here and the specified-duty figures mostly are not.
Hitachi Ultrastar DC HC310 4 TB — The highest duty and reliability figures on this shelf, a non-volatile cache and a published sector format — on a renewed drive with no warranty term at all.