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Vista may require "unproven" drive technology

Reports have emerged that only laptops equipped with hybrid flash memory drives will be compatible with Microsoft's upcoming mobile version of the Windows Vista operating system

Details have emerged this week that Microsoft may be planning to make it mandatory for laptop manufacturers who want to support its operating system to install hybrid flash drives.

A Microsoft document specifying requirements for flash storage led to speculation that hybrid storage would be mandatory for all Vista laptops, from June 2007, but this has been denied by Microsoft. 

However, website Tom's Hardware, recently reported a conversation with Matt Ayres, Microsoft's program manager for Windows client performance which seemed to suggest that laptop makers would have no choice but to support the technology. "Hybrid hard drive manufacturers Samsung and Seagate, as well as other manufacturers... have been informed of the company's decision to make hybrid drive inclusion a mandatory element for mobile systems next year."

Hybrid hard drives save power, as they use solid state flash memory as a large cache, so the hard drive only spins up when the cache is full or needs refreshing, a useful feature with early betas of Vista criticised for draining batteries too fast. Boot-up is quicker too, because the operating system is kept in flash memory

Microsoft's reference material talks about the preformance requirements for hybrid drives, if vendors choose to implement them. The Windows Logo Program Requirements document v 3.01, which specifies what vendors must offer to carry the Windows logo lists hybrid as an option, and specifies that such a hard drive should have a minimum of 50 Mbyte of non-volatile cache must be exposed to Windows, with a throughput of at least 16 Mbyte/s for sequential reads, 8 Mbyte/s for sequential writes, and 4 Mbyte/s for random reads and writes.

Hybrid technology shows promise but is unproven, according to Ken Fisher of ArsTechnica: "Not only is it unlikely that Microsoft would require such a thing, but OEMs would balk at being told that they had to use the more expensive drives merely to get Vista Premium 'stickering'."

Samsung demonstrated a drive with Microsoft last year, claiming that with 1 Gbyte of flash, a hard drive need only spin for around 30 seconds every hour, slashing the power consumption of the drive, normally around ten percent of the energy needs of a notebook. Samsung announced its ReadyDrive hybid products last month which will have 128 or 256 Mbyte of flash, while Toshiba and Seagate have also announced plans for hybrid drives.