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 Microsofts 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.
The other is called ReadyDrive, which uses a flash cache located on the systems hard drive to improve boot times and power usage. ReadyDrives 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 Vistas 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 cant 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.
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 worlds 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—thats 120 days from now—a business notebook would need to include a hybrid drive.
(Just to be clear—or maybe not—Microsofts 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 Microsofts 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 hasnt 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."