Nintendo 64 RGB mod

The Nintendo 64 does not include RGB output by default. However NTSC models can be modded to include RGB output. This does not work for PAL N64s for unknown reasons.

Schematic

Steps

Dismantle your N64 (gamebit required) until the mainboard is exposed. Locate the U4 VDC chip. Identify pins 17, 19 and 21. Pin 13 is labled. Solder 3 wires to the pins and string them out. Attach the three wires as shown in the schematic. Your N64 should now output RGB. Attach your SNES RGB cable.

Source

http://www.gamesx.com/rgbadd/rgbn64.htm