Perhaps you should read this comment on the role of hardware in the Roon experience. A large library will affect the performance of the user interface, because the display is built on the fly by querying the database. And with an Intel Atom, I suspect you are going to find the performance too sluggish to be acceptable, even when it is being used just as a Core. You can certainly forget about using the DSP engine in Roon - the Atom will not be up to handling its demands.