actually the feature does not speed up your ram. These sd cards are not as fast and Ram or DDR. They technology is that any information that is cached to your harddrive would then be cached to your added card therefore causing lag in performance due to the head movement in your harddrive to be less. It not only improves those function but also saves wear on your harddrive. If your actually gonna go out and spend money on a new card I'd suggest getting a usb flashdrive which is faster then most cheap sd cards. Hi speed card and flashdrive will sometimes be marked for this type of use called Ready Boost. Hope this helps.