For many years — including nearly two decades after the NHL made the switch to a 4-on-4 (and later 3-on-3) overtime — college hockey maintained its traditional tiebreaking formula, with all games* that ended in a tie proceeding to five minutes of OT and then ending in a tie for national record keeping purposes.
(*except for the Beanpot... more on this later)
From there, conferences had a mix of ways to break ties for conference points — including adding an extra overtime session of 4-on-4 or 3-on-3 after the end of the OT, and/or going straight to a shootout.