ReadyBoost is a special disk cache service in Windows Vista, 7, 8, 8.1 and 10 that uses fast removable devices, such as USB flash drives, Secure Digital and CompactFlash memory cards for speeding up smaller random disk reads. This can significantly improve Windows performance while many random small files are read frequently or when computer does not have sufficient amount of RAM (Random Access Memory). Traditional hard disk drives and hybrid hard drives (not SSD-s) are up to 80 times slower than removable devices in reading random small files. That's why you cannot use external hard drives for ReadyBoost - no real performance gain is possible.

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And when you try to use it but your PC thinks it will not improve things, it tells you, very good. I've never needed it with 8Gb RAM in my PCs.

3 minutes ago, wgdanson said:

And when you try to use it but your PC thinks it will not improve things, it tells you, very good. I've never needed it with 8Gb RAM in my PCs.

Yes,with 8GB RAM it does not make a big difference, I noticed too. But for PC's low on RAM could use this effectively.

24 minutes ago, ravip said:

Yes,with 8GB RAM it does not make a big difference, I noticed too. But for PC's low on RAM could use this effectively.

You could of course increase your Page File on an SSD to do the same thing. 

12 hours ago, wgdanson said:

You could of course increase your Page File on an SSD to do the same thing. 

 

?? Why would you do that? 

 

The whole point of ReadyBoost, is if one doesn't have an SSD fitted.

Current SSD exhibit far superior performance to an SD card for when it comes to smaller random disk reads. 

No need to mess around with the page file size. Leave it to the OS.