What's an RGB cable? RGB stands for "Red, Green, Blue" and is an analog component video standard for transferring video data. When you add HV to that, it refers to Horizontal and Vertical, and means that those two signals are each given their own wire. RGB offers better resolution and can carry more information than traditional RCA cables, but they can only carry video signals, so you'll need a separate cable for audio. In many applications, RGB is slowly being displaced by DVI and HDMI.