Where the photon server run at ?(Unity or Standalone)

I have a game that going to be released on steam. I made a network system with the Unity's network transport(low level).

And when I run my project on the windows server(desktop view) I see 100% CPU even if I put there empty project.(I know the CPU is low, but not that much.)

So my question is. If I will create dedicated servers for my game with photon, they will run in unity ?(as unity file ?)

Thanks ,
Aviv Oren.