There’s an adjunct to SuperFetch called ReadyBoost. It has been around a long, long time. Back in the day with Windows XP one could right click Computer; click Properties; go to Advanced tab and click the settings for Performance and click Change in the Virtual Memory section. One then selected the (mounted) USB drive, clicked custom size and set it to the maximum permissible of 4096M (assuming the thumb drive had that much free space). Due to how XP handled paging and virtual memory it was not always the case that ReadyBoost back then actually sped things up.

With Windows Vista (!?), 7, 8, 8.1 and 10 a suitable USB port for ReadyBoost must support at least USB 2.0 standard, and USB 3 (SuperSpeed, blue port) is better. In 32-bit versions of Windows and on FAT32 file system devices the maximum is 4 GB of storage. Users steadfastly clinging to older FAT16 file systems will have a maximum of 2 gigabytes. For 64-bit Windows up to 32 GB of storage can be created on a single NTFS-formatted removable drive (even if the drive itself is larger). Windows Vista supports only one ReadyBoost drive at a time. Windows 7 and later allow combining up to 8 different removable devices, so 8 x 32 GB = 256 GB in total storage.

IMPORTANT #1: If Windows is installed on an SSD, ReadyBoost will automatically be disabled because no performance gain can be achieved. Users will see the “ReadyBoost is not enabled because this computer is fast enough that ReadyBoost is unlikely to provide additional benefit” message.

IMPORTANT #2: We do NOT think most of the older minimum speed limits on how fast a ReadyBoost drive had to be apply any more. Verify free space!

IMPORTANT #3: Users should always take special care of the drive used for ReadyBoost because removing or disconnecting it while Windows is running can result in numerous errors (files not found, programs and apps crashing etc). Always Always use the Safely Remove Hardware option (usually an icon in the lower right) to eject ReadyBoost drives properly.