This semi-frequently-updated site attempts to keep a record of which hard drive models, both current and discontinued, utilize what areal density, how many platters, and how many read/write heads.

These attributes are important for several reasons: larger platter density generally allows for higher data throughput performance, but may result in slower seek performance. Meanwhile, less disks and actuator arms mean less moving parts in the drive to eventually break down, and can also lower the heat and noise output of a drive. I research and collect data from online, as well as from drives that I manage to test in real life, and put it all in these lists for you folks to look at.

Anyway, choose which manufacturer made your drive:

Note: I try to keep the information updated and accurate, but I don't always get things right. So, here's a disclaimer: the use of this database is at your own risk, and all information in this database should be taken with a pinch of salt. Also, the contents of this database may change at any moment! For best results (and minimal heartache), please consult multiple sources other than just this site when searching for hard disk platter-related information.

A lot of the data on this site comes out of logical guessing; in other words, from working out which platter density a given generation of drives uses by, for example, analyzing benchmark results; and, with that, using simple math to figure out the platter/head counts for specific drive capacities. This is done instead of purchasing a bunch of drives at once and cracking them all open -- that's expensive and wasteful! These lists were originally created because most of the drive makers don't release such information to the public anymore. (Some older company datasheets - such as those for Seagate's Momentus 5400.2 2.5" HDDs -- do list platter/head counts for each capacity. In those cases, I've pulled their information into the lists for convenience.)

That said, if you see any drives/models that aren't listed or you feel are listed incorrectly, feel free to sound off in either the comments form of the appropriate section or through the Contact form, and I'll see what I can do. If possible, please provide a screenshot of benchmark results from, for example, HD Tune or CrystalDiskMark, that display maximum sustained read speeds performed on a blank (not partitioned) volume, as well as the physical weight (use a scale!) of the HDD(s) in question.

Note 2: The new helium-based HDDs basically all employ seven or more platters and fourteen or more read/write heads. The main point of incorporating helium is to enable such huge amounts of platters and heads to be used, in order to get around the apparent limits (six platters and twelve heads, as of Q2 2016) of "fresh air-breathing" drives. For that reason, along with due to a lack of free time on my part, I will not be adding these helium-based HDDs to the lists.

Note 3: For a while between Q4 2017 and Q1 2018, this site was set to "private mode" in Blogger's settings, thereby completely cutting off public access. This is because I was planning to move the site to a more robust and better-organized content system. That fell through, so the site is now back to "public mode", as it was before. Apologies from yours truly for any inconvenience this may have caused.

Posted by RML527 at 3:00 PM