I saw this on the cover of a book about trains that was at least similar to a magazine:
N700系とはどこが違う?
N700Aに搭載された性能
This is a little confusing:
とは is used to define things. It is often used either in a question asking for a definition or a dictionary entry that actually gives a definition. どこが違う? does not sound like a question asking for a definition.
As for the second sentence, it almost looks like "The ability by which it was loaded by N700A." That is obviously not the meaning of the sentence.
Maybe this is something vaguely in the ballpark of the meaning of that phrase?
What's new and different in the N700 series [of train models]?
The N700A, which is superior in terms of capacity
What is the translation, and in particular, what am I missing here?