Throughout history many intellectuals have shown astoundingly high IQ's though this is the case many look to fictional portrayals of intellectuals through TV shows, Movies, Books and Anime instead of nonfictional collections of information about said intellectuals in time. I must admit I am one of those people as I have been fascinated with humans that have high IQ's, but I prefer to see content gathered and utilised within the multitude of innovative creations being brought to life through media.
Accuracy in the portrayal of characters with high IQ's might be hard to justify as anything fictional is just that 'fictional'. In most of my time I have escaped reality and seen much fictional material throughout my life and of such have thought about the many aspects regarding this question quite a bit, in my honest opinion the main issue in portrayal is human diversity which occurs through the many factors in ones life relating to nature and nurture. IQ is only one facet of one's overall intelligence and most portrayals in media reveal a diverse array of personalities stemming from not only IQ but EQ.
Now when you refer to IQ in your question do you mean to disregard or regard to the many other facets of intelligence such as EQ? Either way it is included within the many portrayals in media as they cannot only have an intelligent character whom has a high IQ without showing the many other facets. Now a high IQ is commonly known to be above 160 that is around Einstein's level, and an Intelligence Quotient is: "A number representing a person’s reasoning ability" (measured using problem-solving tests) as compared to the statistical norm or average for their age, taken as 100. According to the definition by - intelligence quotient (the oxford dictionary)
In Conclusion, though there are many portrayals through many mediums and the characters vary in personalities they all have great talents in certain fields, a high IQ helps one become an intellectual genius but does not guarantee success. Because of this vast range of portrayals the best way to discern the way a person with a high IQ thinks and acts is to watch / read a lot of variations to reveal the common attributes and make concise conclusions on the matter.