WD's Black 4TB hard drive reviewed

SSDs get most of the attention, but mechanical hard drives are still a big part of the PC storage industry. Their capacity expands with each new generation, driving down the cost of a gigabyte to just pennies—a full order of magnitude lower than even the most affordable solid-state drives. Thanks to higher bit densities, each new family of mechanical models still tends to offer better performance than the last. Drive makers seem to be paying more attention to acoustics, too, resulting in ever-quieter noise levels.

There is one category in which mechanical hard drives are getting worse, though. Just a few years back, three- and five-year warranties were common. Then, in 2011, Seagate and Western Digital both cut the coverage for most of their internal drives. Two years became the new norm, ...