INTRODUCTION

    Ever since the very first consumer SATA SSDs made their debut just under 20 years ago there have been many in the industry who supported the notion that mechanical disk drives (HDDs) would cease to exist sooner rather than later. SSDs have always offered immensely higher read & write performance, far lower access times and the lack of mechanical parts usually meant better reliability so in a way that made sense. Still, I was always skeptical about that for two main reasons, capacity and cost and well, it's now 2025 and HDDs don't seem to be going anywhere. Earlier this year Seagate unveiled their latest 30TB HDDs aimed towards Data Centers and professionals and with me I have the Exos M (3+) model.

    Seagate is a global leader in mass-capacity data storage, having delivered over 4.5 billion terabytes of capacity over four decades. From edge to core to cloud, Seagate builds trust in data by delivering scalable, sustainable, and secure storage solutions. Learn more at www.seagate.com.

    The brand new Exos M hard disk drives by Seagate are helium sealed models powered by CMR (conventional magnetic recording) technology paired with HAMR via their Mozaic 3+ technology. The Mozaic 3+ technology was unveiled by Seagate a few years back (they've been working on it since long before 2016) and what it basically does is to allow for more data density than ever before while at the same time improving reliability and reducing power consumption (thus carbon footprint). In order to achieve this result Seagate is using superlattice platinum-alloy media for the platters together with a plasmonic writer (nanophotonic laser, photonic funnel and quantum antenna combination), Gen 7 spintronic reader and a 12nm integrated controller. Seagate has plans for 4TB, 5TB and 6TB capacities per platter in the coming years which compared to the 3TB maximum for PMR/CMR drives is also a huge improvement (yes, the 30TB capacity Exos M model features a total of 10 platters). As for specifications the platters of the Exos M 30TB spin at 7200RPM, it has 512MB of multi-segmented cache and has a maximum sustained transfer rate of 275MB/s. Finally, Seagate covers the Exos M with a 5-year limited warranty and reports an MTBF (meantime between failures) of 2.5 million hours with a reliability rating of 0.35%.