you do not need a multi-pc setup in order to run ATVO for your broadcasts. Since ATVO is also (but not exclusively) made for professional users we needed to implement an option that allows users to run a multi-pc setup as well. The benefit of a multi-pc setup is that you can off-load the iRacing computer from other tasks such as stream encoding. I think it is safe to say we have a lot of users who run a single pc setup just fine :)