It takes a very massive star, like this one, only about 10 million years to use up its core hydrogen (compared to about 8 billion yrs for the sun). Then helium fusion begins and is used up even faster than its hydrogen was.
For a very massive star, a white dwarf is not the endthe star is just getting started! Fusing carbon into neon is the next step. Fusing heavier and heavier elements faster and faster, a monster star completely runs out of fuel in only a few million yearslive in the fast lane, die young.