Have you thought about a 6 core i7 or 8 or more Xeon cores?

Consider the number of uncompressed 1080 cameras.
Consider if you use wireless cameras the H.264 decoding from those sources need more resources than uncompressed sources.

Recently one Wirecast user informed me they were able to use a JVC HM200 wifi feature to send to Wirecast Pro Webstream plugin. That means one might be use a good "prosumer" camera to wonder around an event space without having to use a Teradek Cube. The decoding would like use more resources than using an HDMI into card though.