Re: the 50MHz, it lets me drive a number of LED panels directly with fairly long ribbon cable runs. The goal is to run displays at 161 Hz refresh rate (23 * 7 which are both prime factors that aren't in 60 or 50 so the refresh rate won't "beat" with local illumination).

This frequency determines how many panels I can run from a single "port" which ultimately determines the maximum resolution I can use for a display.