Looking at hardware I have lying around and thinking this Pondesk unit with a Intel Atom CPU E3845 CPU is certain a low powered unit.
Would you expect with pfsense 23.01 installed, probably 50 devices and OpenVPN running it’ll be quick enough. I do hope to add and learn Snort in due course.
Currently I have a Dell R220 in the loft rack, which is probably using 20-25w and idle most of the time.
Virgin Media 200Mb connection, sadly no 1Gb in my area yet.
It would probably route fine, but with a CPU Mark score of 1058 OpenVPN would be slow as well as Suricata
Netgate has some hardware and speed comparisons
Got a 1240L v3 Xeon on the Dell. For the power saving, sounds like too much Performance loss. Will test, but think we know the answer
Connection up is 20mb sorry, forgot to add that.
Will test etc. DCO mentioned in your 23.01 video. I must get round to looking at wireguard too for knowledge