Ready Boost on vista is actually just virtual memory. here is how to set ready boost in XP:
1. right click computer, than click properties,
2. go to the advanced tab, click settings for performance,
3. go to the advanced tab in the perfromance options window, than click change in the virtual memory section,
4. in the drive selection, select your flash drive, click custom size, and set as much as you like.
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