The Commodore 65 had as its beating heart an innovative CPU called the 4510, which was born as an evolution of the 6502 line via the 4502. The addition of new operating codes and improved clock performance led to an evolved CPU representing the point jewel for the era of 8-bit processors with 3.54 Mhz speed. The designer was engineer Victor Andrade who later migrated to the development sections of the famous AMD. You can also see here the original CPU concept drawing from the Commodore plotter