It has been almost exactly two years since I last wrote a "Terabyte Update." Recent market perturbations brought about by the Coronavirus outbreak and its effect on China make this a good time for the update because many think electronics pricing will rise as a result.

Here's the view as of today.

The last column in this table, which I dub "HD Advantage," shows how much less a conventional hard drive costs compared to an SSD. This, to me, is the most telling calculation. In this edition of the update we see that hard drives are still substantially cheaper than SSDs but that the gap is far less dramatic than in previous years.

This represents one of the most interesting comparisons I've seen since I began this informal series. Here are the key points.

• Smaller conventional hard drives have hit something of a floor, there being almost no difference in the cost per gigabyte in the last two years. I round up to the nearest cent.
• Hybrid drives now match conventional drives in cost. I attribute this to the dramatic drop in SSD costs, which make SSDs much more attractive on their own.
• SSD costs have nose-dived, halving the HD Advantage.
• Memory cards are much less expensive after only two years.
• DDR3 RAM is half the price of two years ago.

For a little historical perspective, here is the table I began in 2007 showing the advantage of buying a 1TB hard drive instead of smaller drives. This is where the original name "Terabyte Update" for this article came from; SSDs were not yet in the picture in a meaningful way.

Probably the most interesting fact from this table is a 1TB drive cost $90 in 2009 but two years later cost $140. This corresponded to the terrible flooding in Thailand that ruined a number of factories and thus caused dramatic, worldwide shortages of hard drives.

Predictions?

I certainly do not see the demise of mechanical, rotating memory devices any time soon. They still have one big advantage - they're big. 16TB drives can be had for about $400 or an impressive 2.5¢/GB. The largest SSDs available are less than half that size and the most popular size today is 2TB. 4TB SSDs cost roughly 16¢/GB, yielding an HD Advantage of 7x.

Unless conditions in the PACRIM create supply problems, I think solid state memory devices of all types will continue to fall in price.

Hybrid drives will fade out. As the HD Advantage gets smaller, folks will simply opt for an SSD. I think the fact that hybrid drives now cost almost exactly the same as conventional hard drives makes this inevitable.

Note: I checked prices on 3.5", 7200rpm Seagate Barracuda hard drives; SanDisk SDHC Class 10 memory cards; Crucial's MX series SSD products; and Crucial's RAM products. Previously I used pricing for Intel's SSDs.