How SOC became real?

 Integrating the whole system on a single chip is not a easy task,Then how it happened?

                    The answer is Moore's law...

As per Gordon Moore's prediction the number of transistors in a chip was doubled every 2 years ,This leads the way to integrate billion  transistors in a single chip.

                                Intel's sandy bridge = 1.16 billion transistors
                                Intel's ivy bridge      = 1.4 billion transistors

                                Your SOC =  ???? transistors ????