I have an update on that poem I was looking for.
I finally found a single reference to this poem, through Google Books, in The Columbia Granger’s guide to poetry anthologies, a book which is itself a listing and review of other books. The poem is called “Where the Neuter Computer Goes Click”, and it was contained in the anthology Of quarks, quasars, and other quirks: Quizzical poems for the supersonic age, edited by Sara Westbrook Brewton, John Edmund Brewton, and Quentin Blake, published in 1977. That’s not where I encountered it: as I mentioned, I read it in a literature textbook.
The anthology is out of print, but used copies are really cheap, so I went ahead and bought one.