I read a study that put people in a dark room with a strobing LED and told them to dart their eyes left and right. 1000Hz was the limit before everyone stopped seeing glowing dashes and saw a solid line streak instead.
I found most of the information on Wikipedia[0], and the limit seems to be at about 80hz, but together with movement, some people can see stroboscopic effects up to 10khz.
[0] https://en.wikipedia.org/wiki/Flicker_fusion_threshold#Strob...