Users running the latest iteration of the Windows client will be able to add an extra 256 GB of memory cache in order to handle the overload on the physical RAM installed on their computers. Just as it was the case with Windows Vista, when the feature was first introduced, ReadyBoost in Windows 7 enables end users to turn to any flash memory device from a USB flash drive to an SD card, in order to get extra memory cache for their machines. Specifically in scenarios where computers are dealing with limited amounts of RAM, ReadyBoost can palpably increase the PC's performance.
“Windows 7 has improved the capabilities of ReadyBoost over Windows Vista, including: Maximum cache size has been increased from 4GB to 32GB. Note that to utilize a memory cache of greater than 4GB, the flash drive needs to be formatted with either a exFAT or NTFS file system. Support for up to 8 ReadyBoost devices simultaneously on the PC. Windows Vista only supported a single ReadyBoost device per PC. The ReadyBoost cache can be used during boot to improve startup performance,” revealed a member of the Global Escalation Services.
Windows 7, just as its precursors, will turn to the hard drive to store data, once it can no longer stash it into the physical memory. If the RAM is saturated, storing and accessing data from a USB device is much faster than when the system turns to traditional HDDs, therefore the performance boost. This is, however, not valid for newer computers with Solid State Drives, as there is no difference between the SSD and the USB device in terms of accessibility speed.
“The best option, if possible, is to upgrade the physical RAM to increase system performance. However, when this isn't an option or if you have some extra space on a flash drive that you are not using, ReadyBoost is there as an alternative. A prime example of where ReadyBoost shines are Windows 7 netbooks that only have 1GB of RAM installed. Having a ReadyBoost cache of 2-4 GB will have a noticeable effect on system performance,” the Global Escalation Services team member noted.
Windows 7 RTM ReadyBoost 256 GB of Memory Cache Support