An asynchronous high-performance low-power 5-port network-on-chip (NoC) router is introduced. The proposed router integrates low-latency input buffers using a circular FIFO design, and a novel end-to-end credit-based virtual channel (VC) flow control for a replicated switch architecture. This asynchronous router is then compared to an AMD synchronous router, in a realistic advanced 14nm FinFET library. This is the first such comparison, to the best of our knowledge, using a real synchronous router baseline already fabricated in several commercial products. Initial post-synthesis pre-layout experiments show dominating results for the asynchronous router, when compared to the synchronous router. In particular, 55% less area and 28% latency improvement are observed for the asynchronous implementation. Also, 88% and 58% savings in idle and active power, respectively, are obtained.