I appreciate the responses to my post. My details are posted at: Will rPi 3B+ or 4 be enough to control thermostats?
I have several 3B+ devices collecting dust, so I thought it might make sense to use one to replace the AMD box and use less energy. It’s really hot in the summer, so a cool 3B+ is appealing. I also would like to repurpose the AMD box for OnlyOffice
I suspect that the 3B+ CPUs are more than enough and that the bottleneck is RAM. I recently had a good success with another 3B+ outfitted with NextCloudPi on a USB 2T SSD. Really nice that the 3B+ is configured out of the box for USB booting.