I'm sorry, I apologize in advance, I don't mean to be obnoxious, but....
I was a member of MENSA since high school, just haven't paid my dues in a long time. Gotta get back to doing that...
I do remember hearing of a few actors, however:
(for comparison, Stephen Hawking, I heard, was only around 160)
-- James Woods, 170 (yes, an MIT grad)
-- Gena Davis, 165 (grad of Boston University, my alma mater)
-- Emma Dumont, ??? (the actress on Aquarius, Bunheads, and The Gifted)
-- Asia Carrera, 161 (porn actress, and played Vince's girlfriend for a season on Entou