Hard disk drives in 2.5" form-factor are no longer solely used inside notebooks PCs, but are also utilized in servers and some small form-factor desktops. As the latter get smaller and all-in-one desktop PCs get, new processors, lower power consumption and a thinner, smaller storage alternative to existing 3.5" hard drives will help create a viable market for 2.5" desktop HDDs beginning in 2013, according to analysts from IHS iSuppli.

Shipments of 2.5" HDDs to all-in-one PCs are forecast to reach approximately 1 million units in 2013, up from virtually zero this year. Shipments will then increase to 3 million units the following year and move up steadily until they hit some 7 million units in 2016. The HDD market for all-in-one PCs will continue to be dominated by 3.5" discs, with shipments by 2016 estimated at 31 million units, but growth will be much slower for the segment during the same period.

Two disadvantages of the 2.5" HDD are speed and price. Most 2.5" drives typically run at 5400rpm spindle speed, compared to 7200rpm for the 3.5". The 2.5" also sells at slightly higher prices than the 3.5" as a whole, although the gap in price can be narrowed if 2.5" volumes become significant.

Nonetheless, enough positive factors are present to push growth overall for the 2.5" drives. As a result, the 2.5" will represent approximately 4% of the all-in-one desktop PC market by next year, and then go on to account for 18% of the all-in-one market by 2016. And as capacity and speed continue to improve and costs go down, the 2.5" HDD is expected to take share away from 3.5" HDDs in the traditional desktop PC market, IHS iSuppli predicts. The 2.5" hard disc can enjoy about four to five years of uninterrupted growth before low-priced, high-density solid state drives become competitive.

The 2.5" HDD is used widely today in a variety of products, including mobile or notebook PCs, external hard disk drives and enterprise applications such as servers and storage systems. Their advantages over conventional 3.5" HDDs include a smaller form factor, lower power consumption and higher endurance.

Of late, however, the 2.5" drives have also become attractive and desirable for desktop PCs, especially among all-in-one computers. With maximum capacities of 1TB, the drives are proving very attractive for all-in-one PC makers in their next-generation designs. All-in-one PCs that have the potential to adopt the 2.5" HDD as their storage medium include the iMac from Apple, TouchSmart from Hewlett-Packard, Series 7 from Samsung Electronics, IdeaCentre from Lenovo, Top Touchscreen from Asus Eee, and all-in-one desktops from Vizio and Acer.

With demand for all-in-one desktop PCs expected to grow, future market prospects for the 2.5" HDD appear encouraging, IHS iSuppli believes. Compared to conventional desktop PCs, all-in-ones possess superior features and performance, brought about by advances in processors, the adoption of NAND flash and the thinner HDD size. As such, all-in-one desktop PCs can extend the current markets for 2.5" HDDs covering notebooks, external hard drives and the enterprise, allowing the thinner and smaller drives to penetrate the desktop space.

Tags: HDD, 2.5", Business, Seagate, Western Digital, WD, Hitachi GST, Toshiba