High Performance Computing (HPC) delivers huge processing performance, and plays a key role in the national welfare and the people's livelihood. As the source of computation power, high performance processors mostly determine the overall performance of a HPC system, and are being intensively studied in many countries nowadays to maintain a competitive edge in the HPC domain. This paper provides a review of the state-of-the-art processor architectures from mainstream processor designers like NVIDIA, Intel, and AMD. We carry out the review in terms of computation resource organization, memory subsystem design, and the connection technology among multi-cores. Based on the analysis, we summarize the mainstream trends in high performance processor design. We believe that this paper can serve as a reference for future research on HPC oriented processor designs.