HP Begins Transition To 2.5-inch Disk Drives

Hewlett-Packard and leading vendors of hard disk drives on Wednesday unveiled plans to begin the transition to next-generation 2.5-inch small form-factor disk-drive technology for servers and storage.

"In the hard-drive industry, transitions take a long time," says Rich Palmer, director of product marketing for storage, networking, and infrastructure for the ProLiant server business at HP. "In the early '90s we transitioned from 5.25-inch to 3.5-inch hard disk drives, and this next step is expected to take us into the next 10 years."

The new 2.5-inch hard disk drives were developed by Fujitsu, Hitachi, and Seagate, and will be used by HP in upcoming ProLiant server and storage products, Palmer says. The 2.5-inch, 10,000-rpm hard drive is expected to be available in HP ProLiant servers by midyear. The drives are also expected to be used in HP's BladeSystem, Integrity, and StorageWorks product lines in 2006. Also in 2006, HP plans to offer 2.5-inch, 15,000-rpm hard drives.

HP currently ships more than 1 million hard disk drives per quarter, Palmer says.

At the same HP is transitioning its product line to 2.5-inch hard disk drives, it also will migrate from traditional parallel SCSI interfaces to Serial Attached SCSI, or SAS, interfaces, he says. "Customers have been loud and clear that they want to make this transition at one time," Palmer says. "They want to move to the small form-factor drives and SAS at the same time, rather than having to complete two separate transitions."Over the next year, the new drives and Serial Attached SCSI interface will be offered as an option to the ProLiant line of servers, and then next year the new technology will be factory installed, he says.

The advantages of 2.5-inch drives include the ability to create higher data density in smaller areas. The smaller drives also require half the power of 3.5-inch drives while generating 70% less heat, Palmer says.

Another advantage is scalability. With parallel SCSI, there's a limit of 14 drives on a shared 320-Mbps bus. With Serial Attached SCSI, as many as 128 drives can be placed on a single bus, with each drive having access to as much as 300-Mbyte-per-second bandwidth.

HP also plans to offer a 3.5-inch, 15,000-rpm Serial Attached SCSI option.