The intra-frame coding in H.264/AVC has made significant contribution to the enhancement of coding efficiency. However it brings about a heavy computation burden in the rate distortion based (RD) mode decision (MD) process. Although the real-time encoding of 1280-720p signals is realized in recent works with existing algorithms, for higher resolution e.g. 1920-1088p some hardware-oriented fast algorithms are necessary. Yet so far few of the many proposed fast MD algorithms have seen successful hardware implementation. This paper presents a novel VLSI design (15.8k gates@200MHz, with TSMC CMOS 0.18m technology) of an edge based fast intra MD algorithm which can constantly reduce about 66% of the RD related computation with a negligible quality loss. It is expected to be utilized as a favorable accelerator hardware module in a real-time HDTV (1920-1088p) H.264 encoder or MPEG2-H.264 transcoder.