sleep and missing readyboost file

[William Tall]

Vista Home Premium 32 bit
2gb usb flash drive setup for readyboost
I use the sleep button on my keyboard to sleep the unit and sometimes when I
bring it out of sleep the readyboost cache file disappears . I unplug the
drive put it back in and the cache file reappears . Very annoying because
the readyboost does help performance .
Thanks ahead of time for any help .
Will

 

[Bob]

In "Change Advanced Power Settings" select "disable" under USB settings.

 

[William Tall]

Even after setting USB to disable sometimes the cache file disappears when
woken from sleep mode .
Will