ReadyBoost is a disk caching technology first included with Microsoft's Windows Vista operating system. It aims to make computers running Windows Vista more responsive by using flash memory on a USB 2.0 drive, SD card, CompactFlash, or other form of flash memory, in order to boost system performance.
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For a device to be compatible and useful it must conform to the following requirements:
* The capacity of the removable media must be at least 256 MB (250 after formatting)
* Devices larger than 4 GB will have only 4 GB used for ReadyBoost
* The device should have an access time of 1ms or less
* The device must be capable of 2.5 MB/s read speeds for 4 KB random reads spread uniformly across the entire device and 1.75 MB/s write speeds for 512 KB random writes spread uniformly across the device
* The device must have at least 235 MB of free space
* NTFS and FAT,FAT32 are supported