Questions about rendering and performance


I would like to render short (few minutes) videos with unreal cinematics.
I have several questions:

  1. What is the recommended specs for a workstation that would render movies as fast as possible?
  2. Is there a limit to how many videos can be rendered at the same time?
  3. Will strong GPU or multi-GPUs help increase the rendering speed? or should we invest in a strong CPU?

Thanks in advance!