40GHz lol...
That's like saying "hey, if we all take separate cars, we should get there in a fraction of the time!"
multi cores only work when the goal is multiple different things. And even still, those different things are being done, though simulataneously, at the same clock speed. If 10 people row a wide open field, it gets done in a 1/10 of the time. But for 10 people to climb up a ladder, you're still only as fast as the slowest person.