PerfectCache 

PerfectCache implements patented block-level caching technology to raise system performance beyond that of the Windows file-level cache alone. PerfectCache breaks the disk I/O bottleneck by using the PC's system memory to store the most frequently used data, executing read and write requests from memory rather than from disk. PerfectCache's core component is a storage volume filter driver which resides in the storage stack just above the storage volume class drivers.

PerfectCache intelligently stores frequently used disk data in system memory. The memory used to store the data is called a cache. PerfectCache intercepts requests for disk data and, when possible, fulfills the request using the cache instead of requesting data from the disk. When data is read from or written to the cache, the performance is similar to a RAM disk (extremely fast).