The P5 microarchitecture was designed by the same Santa Clara team which designed the 386 and 486. Design work started in 1989; the team decided to use a superscalar architecture, with on-chip cache, floating-point, and branch prediction. The preliminary design was first successfully simulated in 1990, followed by the laying-out of the design. By this time, the team had several dozen engineers. The design was taped out, or transferred to silicon, in April 1992, at which point beta-testing began. By mid-1992, the P5 team had 200 engineers. Intel at first planned to demonstrate the P5 in June 1992 at the trade show PC Expo, and to formally announce the processor in September 1992, but design problems forced the demo to be cancelled, and the official introduction of the chip was delayed until the spring of 1993.