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Last summer, industry and customer conferences were abuzz with presentations about new flash memory caching technologies that would improve the user experience of Windows Vista, especially for mobile desktops. And storage vendors climbed on board with preannouncements of “hybrid” flash-enabled drives to support the plan.

However, with Vista now in general release, the timing for hybrid hard drives may not meet the early rosy predictions. It appears that many system vendors are still looking for someone else to be the early adopter of this technology.

As a result, Microsoft in late 2006 quietly revised its standard definition for a “Premium” Vista notebook, pushing back by at least a year its requirements for a hybrid drive.

There are two flash cache architectures associated with Vista, and both take advantage of Microsoft’s SuperFetch intelligent memory management technology. The first is ReadyBoost, which uses a cache connected to the Vista notebook or desktop, such as an ordinary USB thumb drive, to speed up overall system and application performance.

Click here to read more about SuperFetch and the Vista flash caching schemes.

The other is called ReadyDrive, which uses a flash cache located on the system’s hard drive to improve boot times and power usage. ReadyDrive’s expanded flash caching is dubbed “hybrid” HDD (hard disk drive) by the industry.

On the ReadyBoost front, many owners of thumb drives are finding that only a portion of their collection can match the performance and capacity requirements of ReadyBoost. To sport a ReadyBoost logo, the thumb drive will need to have a capacity of 512MB or greater, and provide throughput of 5MB per second for random 4K reads and 3MB per second for 512K random writes.

Developer Grant Gibson offers a compatibility list on his site. Readers submit the results of their tests. He recently reported that of the 364 devices tested as of Jan. 25, 59 percent work with Vista’s ReadyBoost.

One issue that may be adding to the failure problems with the thumb drives is that the flash memory used must be from SLC (single-level cell) technology. This architecture offers more robust performance than the multilevel cell flash entering the market. However, users can’t tell the levels from the outside.

Microsoft is naturally gung ho for these flash technologies, and it launched a marketing campaign on OEMs and the media last summer and fall. The beefier caching can improve the Vista experience (always a good thing), and the schemes address directly some specific knocks on of Windows XP performance.

Vista appears to want all the memory that you can throw at it, flash or standard DRAM. Will customers balk at purchasing notebooks with multi-gigabytes of RAM? Click here to read more.

Whereas Vista customers can take a thumb drive out of the desk drawer and try out ReadyBoost right away for themselves, the hybrid hard drives needed for ReadyDrive are still under development.

Several storage companies announced hybrid drives in mid-2006, including Samsung Semiconductor, the world’s leading manufacturer of NAND flash as well as a maker of hard drives, and Seagate Technology, the leading HDD manufacturer.

Microsoft expected to drive the adoption of hybrid drives by mobile system vendors with an aggressive qualification program for Vista stickers. To sport a Premium System logo in June 2007—that’s 120 days from now—a business notebook would need to include a hybrid drive.

(Just to be clear—or maybe not—Microsoft’s Vista logo program defines a “mobile system” as one that “can be physically carried, have integrated display and input devices, and have a battery that provides continuous operation when the unit is not plugged in.” That seems clear enough, but the company then makes a distinction between “mobile” systems and “ultra-mobile” and ultraportable” systems under the plan. Regardless of the “ultra” complications, we can be confident saying a mobile system would be big enough to have a 2.5-inch hard drive in it—that was the size of drives that storage vendors said they would add a flash cache to.)

At the same time, despite Microsoft’s logo deadline, it appears that system vendors were looking at each other and wondering which would go first to market with a hybrid drive.

Certainly, no notebook vendor has announced a model with a hybrid drive—of course, no such drive is available yet from manufacturing, but that hasn’t stopped them before. And analysts I spoke with this week said that they had not heard any such plans for support of the hybrid technology in vendor briefings.

Meanwhile, the June 2007 requirement was delivered to partners in presentations at major storage and developer conferences, such as the 2006 WinHEC (Windows Hardware Engineering Conference) in May, the July TechEd conference and the annual Intel Developer Forum in late September. The enforcement date held firm.

However, in mid-November, Microsoft relented, and the June 2007 requirement for hybrid disk drives was pushed back a year. A note on the logo program site told that the table of requirements had been updated to “reflect the future enforcement date of Hybrid Hard Disk Drives for Premium Mobile systems to June 1, 2008.”

Next Page: Storage vendors: Drives will be ready in Q1.

Microsoft pointed to its storage partners.

“Based on feedback from partners, Microsoft moved the requirement [for the Windows Vista Premium PC logo] out, as frequently happens if Microsoft does not feel partners have enough time to absorb, or the technology won’t be available in production volumes in time,” a company spokesperson said.

However, a number of storage vendors said drives would be ready in the 2007 time frame.

According to Michael Hall, manager for Seagate’s desktop and notebook storage press relations, the company is on track to ship its hybrid drive toward the end of the first quarter.

In addition, Don Barnetson, director of flash marketing for Samsung Semiconductor, said in late 2006 meeting that the company was expecting a Q1 release for its hybrid drive.

Toshiba, which makes notebooks, hard drives and flash (the No. 2 manufacturer), has hybrid sample drives and prototypes out at “various OEMs and infrastructure builders,” according to Patty Kim, product marketing manager with Toshiba America Information Systems’ Storage Systems division. She wouldn’t set a date for volume shipments.

So, whether there will be enough production to fill demand for hybrid drives may be less than an open question. Still, at the moment, there appears to be little to no downstream demand from the mobile system vendors.

The storage industry is addressing the demand situation with the Hybrid Storage Alliance, which was announced in early January at the Storage Visions conference in Las Vegas. The founding members include Fujitsu Computer Products of America, Hitachi Global Storage Technologies, Samsung Electronics, Seagate Technology and Toshiba America Information Systems.

Read more here about the Hybrid Storage Alliance.

The members hope to evangelize the drives with existing customers as well as with system vendors.

“The purpose of the association is to educate the market and make people comfortable with the benefits of hybrid disks,” Kim said. She’s on the list of spokespersons for the alliance and said acceptance of hybrid drives requires a coordinated effort.

“People haven’t seen demonstrations of the drive,” Hall said. “Once it’s in systems and people see it, it will turn some heads. Then it will take off,” he predicted.

Still, how long will it take for a word-of-mouth campaign to build enough demand to persuade system vendors to build hybrid drives into standard notebooks? Will notebook makers even want to offer hybrid HDDs as an option?

While Vista’s support for these flash technologies has the promise of performance gains and ROI improvement for end users, the technology bumps up against the usual low-ball pricing in the PC market. As system vendors seek to eek out a bit more profit, there’s little pressure to add or support an untried technology that few customers understand or know about, and worse, costs more than ordinary flashless drives.

Everything seemed so easy last summer, when Microsoft marketing managers rolled out the PowerPoint presentations on hybrid drives. And depending on the outcome of the storage education project, Microsoft may need another dose of flexibility when it comes to enforcing the 2008 deadline for Premium Mobile systems.

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