Probably never. Here’s why.
DRAMeXchange is predicting that in 2017 some 41% of laptops will sport SSDs. As the per gigabyte price difference between disk and flash shrinks, the price differential becomes irrelevant at ever-higher capacity points.
Most people have little idea how much storage they use or need. Compulsive music/photo/video folks will use terabytes, but otherwise most users don’t need more than 120GB – and those drives are available for the $50 minimum price that any capacity disk drive needs to be viable.
Small is beautiful
For decades the hard drive industry progressed by making drives physically smaller. Smaller size reduced costs, improved performance and simplified configuration.
That’s why we had drives as small as 0.85″. But flash has killed off form factors under 2.5″.
Performance is sexier than capacity
Flash wins in notebooks and tablets despite a higher cost-per-bit because of its performance (primarily) and space, power and thermal advantages. If one notebook has a $50 disk and the other a $50 SSD, the latter will be obviously faster to consumers and more desirable.
But the external consumer storage market is different. While professionals buy Thunderbolt SSDs for maximum performance and reliability, the small office/home office user sees cost-per-bit and doesn’t require SSD performance – or Thunderbolt.
Even if SSDs fall to 2x disk prices, buyers will continue to prefer low-cost capacity for what are essentially archive applications. The home archive market will get very big because it is cheaper than the cloud. (Why it always will be is another post.)
And 2.5″ drives will remain popular despite costing more per-bit than 3.5″ drives because their size, shock resistance and bus power makes them much more convenient. Convenience sells, even storage.
The StorageMojo take
Yes, 2.5″ drives will lose the notebook market. My guess: 2020 will be the last year for disk-based notebooks.
But the SOHO archive market will save this form factor. Shingled magnetic recording (SMR) is ideal for archiving as it doesn’t handle frequent updates well, and it dramatically improves capacity, helping with the cost issue against flash.
With 4TB 2.5″ USB 3.0 drives running $30-$40/TB online – and 1TB SSDs running $300 and up – disks still retain a huge lead in cost-per-bit. Now vendors need to step up and see what else they can do to tune disks for the consumer archive market.
Courteous comments welcome, of course.