I wired the old amp down in the basement. I can get 3-channel surround out of it. Not bad. The center channel sucks, but that's OK. It does well enough to watch movies.
My old amp has a short somewhere, and shows a "protection" message when you use all five speakers. A bit of internet browsing indicates that I could get it repaired for $100. That's not bad. The amp cost $450 about ten years ago. A new replacement of similar capability would cost $100? You get the idea. Surround sound is nice. Free is nicer.