CPMulator is a program to emulate the CP/M operating system under x86 DOS. The program was developed in 1984 by Keystone Software Development. The company was owned and operated by Jay Sprenkle. The NEC V20 chip released that year was guaranteed to be hardware compatible with the 8088. After reviewing the instruction timing of the math operations and instruction addressing hardware it was determined it could slightly speed up existing 8088 based IBM PC machines. Keystone software started advertising "PC Speedup Kits" in PCWeek magazine. The CPU was socketed in IBM PC's so it could easily be replaced. In practice most programs received a 5% speed increase but those that were math intensive were much improved. One customer reported his monte carlo simulation of a nuclear reactor was so much