Updating multiple displays from a single machine

Updating multiple displays from a single machine

My use case is similar to the lobby display of a small gym: three
displays, each with a different level of refresh:
1. The monthly calendar
2. This hour's schedule of events
3. Streaming video of the current activities
The advice that I have been given so far amounts to having a different
computer to support each display. Ideally, I would want to maintain (e.g.,
assign and change) all of these feeds from a single machine, but not
mirror that display (e.g., so that computer could be used for other
tasks--even better if this is possible on a desktop computer with
windows).
Can this be done, and if so, how?
If not, what's the next-best alternative--and how should I be describing
this problem to get more information?
Thanks!