RGBTOHDMI 12 Bit Extender

The 12 bit boards have the same 8 bit header as the earlier 8 bit boards with the extra 4 bits on another header as there isn't enough room for the full 12 bit header so the extender consolidates this and brings all 12 bits, sync and power outside the case on a single connector. This is only required for computers that have to pick up all 12 bits internally.

(From hoglet67 on github, produced at an international PCBA house)