ReadyDrive is the Windows Vista feature that supports hybrid HDDs. It is supposed to enhance performance by allowing applications to execute more quickly from within the NV cache. Also, utilizing the NV cache instead of writing immediately onto the physical medium allows the drive to stop the spindle motor, which reduces the H-HDD's average power consumption while increasing ruggedness, as the heads are parked. Finally, a drive that doesn't spin does not get very warm and doesn't produce any noise. In theory, a hybrid hard drive could be a clearly better choice than a conventional hard drive.

Application Pinning

If you paid attention to the table on the previous page you'll remember the item "OEM Pinned Data". OEMs are given tools that let them pin specific applications into the NV cache so they will execute faster. We believe that a specific assignment of applications to be stored within the NV cache makes a lot of sense for performance users. Unfortunately, there is no way (yet) for average Joe to determine which applications are pinned into the NV cache.

SuperFetch

All the NV cache memory that is not used for the drive firmware, the write cache or OEM pinned data can be used to accelerate application execution by pre-buffering the most frequently used program data. We found that SuperFetch does indeed make a difference, but you need at least some unused main memory. From our experience the feature has the best effect with systems containing at least 2 GB of RAM. Please read our article "Windows Vista's SuperFetch and ReadyBoost Analyzed" for more information.

With 256 MB of NV cache on the Samsung hard drive, only approximately 135 MB is left for SuperFetch to use. Considering that SuperFetch can quickly fill hundreds of megabytes of main memory, this doesn't seem like a lot. Also, if we compare the performance of a 30 MB/s Flash memory to the several gigabytes per second main memory throughput, using the H-HDD's NV cache to buffer application data seems not too meaningful. However, it might not hurt, either.