computing device vs computing machine

computing device and computing machine both are nouns.

Word	Noun	Adjective	Verb	Adverb
computing device	Yes	No	No	No
computing machine	Yes	No	No	No

As nouns, computing device and computing machine are synonyms defined as:

computing device and computing machine: a machine for performing calculations automatically

Other synonyms of computing device include computer, data processor, electronic computer, information processing system.

computing device (noun)	computing machine (noun)
a machine for performing calculations automatically	a machine for performing calculations automatically