Quote - Windows ReadyBoost can use storage space on some removable media devices, such as USB flash drives, to speed up your computer. When you insert a device with this capability, the AutoPlay dialog will offer you the option to speed up your system using Windows ReadyBoost. If you select this option, you can then choose how much memory to use for this purpose. However, there are some situations where you may not be able to use all of the memory on your storage device to speed up your computer. Some universal serial bus (USB) storage devices contain both slow and fast flash memory, and Windows can only use fast flash memory to speed up your computer. So if your device contains both slow and fast memory, keep in mind that you can only use the fast memory portion for this purpose.

The recommended amount of memory to use for ReadyBoost acceleration is one to three times the amount of random access memory (RAM) installed in your computer. For instance, if your computer has 512 megabytes (MB) of RAM and you plug in a 4 gigabyte (GB) USB flash drive, setting aside from 512MB to 1.5GB of that drive will offer the best performance boost.

Odd that they use 512MB RAM as an example, since Vista uses over a GB.:tongue1:

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