Seagate Ships First HAMR Hard Drives Allowing Monster 50TB And Larger Capacities

hero hamr hard drive render
Hard drives are dead, right? The proliferation of cheap solid-state storage certainly has made the ol' spinning rust largely obsolete for desktop builds and typical consumers, but when you need to store a ton of data in as small a space as possible, you're still not going to beat a hard drive. It looked like that might stop being the case for a while, but Seagate's just started shipping the first HAMR drives at 32TB capacity.

hamr render
Above and top renders from the Seagate YouTube video below.

What is HAMR? It stands for Heat-Assisted Magnetic Recording. Basically, there are two ways you can increase the capacity of a hard drive: either add more platters—the magnetic discs inside the drive—or increase the density of those platters. Seagate's been shipping ten-disc drives for some time now, so the "add more platters" idea is pretty much spent. Instead, the goal is to increase bit density.

The problem is, when you increase the density you add all sorts of issues; most notably, the magnetic state of bits starts to affect those of bits around it. You can work around this issue by using a new material with superior stability, but this makes it impossible to record to. HAMR works around this issue by using a laser diode to heat an infinitesimal fraction of the disc before recording. This excites individual bits and makes them briefly writable, allowing the disc to be much denser.

astc technology roadmap

HAMR's been a long time coming. Seagate's been talking about the technology since around 2002, and started doing test prodcution in 2018, but it's only now making its way to market some 21 years after conception. Seagate expects standard perpendicular magnetic recording (PMR) and shingled magnetic recording (SMR) drives to stay on the market for some time, but it'll be HAMR drives that offer the really high capacity which makes the hyperscale cloud operator guys drool.


Dave Mosley, CEO at Seagate, says that he expects volume production of HAMR drives to ramp in the early part of next year. Despite that, the company still plans to introduce at least one more generation of PMR and SMR drives, including disks of 24TB or larger capacity using PMR with Two-Dimensional Magnetic Recording (TDMR) heads, as well as drives that combine TDMR with shingled recording.