History and Purpose
ReadyBoost was introduced in Windows Vista as a way to use a USB flash drive as a cache between the hard drive and RAM, giving low‑end systems a noticeable speed boost.
How ReadyBoost Worked
The feature allocated a portion of the flash drive—typically between 1× and 2.5× the size of installed RAM—and stored frequently accessed files there. Random reads from flash were faster than from a mechanical HDD, while sequential speeds were still lower than RAM.
Factors Leading to Its Decline
- Modern PCs ship with 8 GB+ of RAM, making the cache benefit marginal.
- Solid‑state drives provide far superior random‑read performance, rendering flash caching unnecessary.
- Windows memory management and storage drivers have become more efficient.
Current Relevance
ReadyBoost is only available on Windows 10 systems that still use an HDD and have very limited RAM (≈1 GB). On Windows 11 it has been removed entirely.