If we assume it is possible to simulate a universe. A piece of hardware with just enough power to simulate one universe will eventually be simulating an infinite amount of them, through more of these machines being built inside of the simulated universes.
Each simulations will have to be more simple than what simulate it. At the end it will be too simple to simulate anything, and then this will result in a finite number of simulations.
It can be assumed that if it is a perfect simulation of our universe, then the quantum computer that was created in the original universe would eventually be created in the simulated universe causing a sort of cascading effect of infinite simulated universes.