I know exactly what story the OP was asking about and I think it was called Xenophobe, but I can't find it either. Humans had nanotech films on their brains for interfacing with computer systems, eastern culture had become dominant, the aliens used Silver Surfer-looking nanotech mechs that split into smaller mechs once defeated and at some point, humans came into contact with a third alien race using biotech that also wanted to help defeat the antagonist aliens. The ending had a twist about the true nature of the attacking race.

Edit: I FOUND IT! IT WAS CALLED "[WARSTRIDER][1]", BY IAN DOUGLAS! I clearly remember the cover having the word "Xenophobe", big and bold, on the cover, though, along with a huge black/silver alien thing looking like the creatures from Pitch Black, bearing down on a guy.


  [1]: https://www.goodreads.com/book/show/553590.Warstrider