Shopping for single platter hard drives - Part 2

Sometimes, when buying a hard drive, you need gobs of gigabytes. But when total storage space is not a prime consideration, opting for the simplest mechanical design, a single platter, makes sense from a Defensive Computing perspective. 

My previous posting was about trying to glean the number of platters inside a hard drive based on assorted specs from the manufacturer. All things being equal, a single internal platter should be more reliable because there is less that can go wrong. It may also offer battery life and heat benefits.

Within the Seagate 7200.12 line of 3.5 inch hard drives, the specs showed that the six models fell into two camps. The two high capacity models share one specification profile as do the four lower capacity models.

Based on the weight of the drives, as well as their height and the power needed to keep them spinning, it seemed  that the four lower capacity models have fewer platters than the two higher capacity models.

And they do.

But, even though the four lower capacity models have identical weight, height and power requirements, they are, nonetheless, physically different.

The two lowest capacity models (160GB and 250GB) have a single disc platter while the 320GB and 500GB models have two platters. The two largest capacity models (1TB and 750GB) have four disc platters.

How do I know this? Mike Hall of Seagate said so.

Why the mystery? Why aren't the number of platters included in the published specs? He doesn't know.

This is not to pick on Seagate, I've looked at other specs for hard drives and they don't normally include the number of platters.

A quick look, for example, at the specs for the Western Digital Caviar Blue line shows they also fail to include the number of platters. I'll see if anyone from Western Digital can shed some light on this.

The specs for the Hitachi Ultrastar A7K1000 line do include the number of platters (referred to as "data disks"). There are three models starting at 500GB. The 500GB  model consists of three platters, the higher capacity models have more.

However, the Ultrastar A7K2000 line by Hitachi, which also starts with a 500GB model, does not include the number of platters in its specs. Likewise, the specs for the Hitachi Deskstar 7K1000.C line do not include the number of platters. I'll also try to contact Hitachi to see if they offer any single platter models.