The following are requirements for USB flash devices enhanced for
ReadyBoost:
• USB flash drives themselves and the host controllers they are inserted
into must both use the USB 2.0 standard.
• USB flash drives must have at least 230 MB of free space.

Flash Performance
Flash storage devices must meet minimum performance requirements to support
ReadyBoost, including 2.5 MB/s throughput for random 4K reads and 1.75 MB/s
for random 512 K writes.
Higher performance requirements must be met for the device to be designated
as “enhanced for ReadyBoost”: 5 MB/s for random 4K reads and 3 MB/s for
randmon 512 K writes. Microsoft recommends that users use devices enhanced
for ReadyBoost

(from "Windows PC Accellerators")

"Bert" wrote in message
...
Is there a certain size or speed that my flash drive needs to be to take
advantage of ReadyBoost?