I use a NUC clone with a J4125 Celeron as a Debian file server and it hovers just under 3W. These tend to have only one Ethernet port so you will need to add ad

I use a NUC clone with a J4125 Celeron as a Debian file server and it hovers just under 3W. These tend to have only one Ethernet port so you will need to add additional ports on USB for use as a router.