According to Microsoft, Windows Vista will require at least 512MB RAM memory and 1GB or more to run smooth. DailTech discusses some of the new features of Windows Vista and talks a bit about the memory industry. They also predict 2GB RAM in desktop PCs may be a lot more common by the end of this year, partly due Windows Vista.
Furthermore, Windows Vista will come with a new feature called Superfetch. With Windows XP, Microsoft included a feature called Prefetch: a dynamic service that preemptively loads files into the pagefile in order to speed up application load time. Superfetch advances further in two steps. Step one is to build profiles of frequently used applications and store those profiles into the pagefile, and system memory. Step two is to pool NAND and all other available memory to move as much of the pagefile as possible off the hard drive and onto the solid state memory. As a result, anyone with a heavy usage profile will have a significant portion of their system memory dedicated to application data.