As we approach the general availability of ultrabooks with the Windows 8 operating system it looks like the largest sales for ultra-thin computers will include a hard disk drive as well as flash memory.

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Last October, for example, the company unveiled a new line of thin MacBook Air notebooks that have no disk drives.

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The Archos G9 Android-based tablet computers contain Momentus Thin (7 mm thick) hard disk drives from Seagate Technology rather than flash memory for long term storage.

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While flash memory in a separate smaller capacity SSD module is playing a role in these new ultra-thin computers the introduction of hybrid hard disk drives with a flash cache inside the hard drive may plan a significant role as well.

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Boasting solid state drive (SSD) like speed and hard disk drive capacity, the new Seagate Laptop and Laptop Thin SSHDs are the most affordable way to increase your laptop performance.

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Seagate, Western Digital and Toshiba are shipping hybrid HDDs targeted for the ultra-thin mobile computer market with up to 8 GB of flash memory and 1 TB hard disk storage.

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Drobo BeyondRAID, which provides thin provisioning, instant expansion, mixed drive size flexibilty, automatic protection levels, dual-disk redundancy, virtual hot spare, and drive reordering.

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