Once again, thanks to Connectix Corp. for this extension that can double or even triple the virtual capacity of your RAM, getting your Macintosh to act almost exactly as it would if you actually added an equivalent amount of physical RAM. However, you still have the physical, installed RAM as a base. Speed decrements may occur at times (especially as you approach the limits of available memory), but they are usually minor. Also note that RAM Doubler works best when you use it to open more programs at once, rather than to assign increasing amounts of memory to a single program. Virtual Memory has to be turned off in order to use RAM Doubler.