IBM founded the Austin Research Laboratory to investigate high-performance microprocessor-based systems. Initial efforts have focused on design for high frequency. This resulted in the completion of a prototype for a 64-bit PowerPC processor core early in 1997. The prototype is expected to run at 800MHz in .25 micron CMOS technology. We discuss clocking strategy, circuit design, microarchitecture, methodology, and the testing strategy needed to achieve this frequency.