An update is available that lets nonvolatile (NV) cache commands be sent to SCSI-class devices in Windows Vista
Intel Turbo Memory (ITM) is an integrated nonvolatile (NV) caching solution. ITM works together with Microsoft RAID, and it introduces support for caching of a RAID device. This NV caching solution requires that NV cache commands be sent to the RAID device.
In Windows Vista, the NV cache commands can be sent only to HDC-class devices. However, many RAID products are Small Computer Standard Interface (SCSI)-class devices. Therefore, the NV cache commands cannot be sent to these devices.
An update is available to let NV cache commands be sent to SCSI-class devices.
For more information on this issue, including potential causes, workarounds, and resolutions, see: Microsoft KB Article KB954943.