There are many many machines out there with x86 soldered CPUs all of them idling at less < 10W. E.g. ASUS PN-series with Celeron CPUs. You can even find them on

There are many many machines out there with x86 soldered CPUs all of them idling at less < 10W. E.g. ASUS PN-series with Celeron CPUs. You can even find them on physical stores. I have a PN40 idles at less than my RPI4b...