OK, the inside or middle VGA plug is for the arcade monitor and the outter is for a PC. The only way you can get the Pc port to display is to have some sort of arcade monitor or jpac type thing plugged into the arcadeMon port. I actually have 2 dead chassis from other monitors that I plug into the breakout cable. the chassis don't even need be powered but plugged in. the same goes for the Jpac card. it prolly has something to do with the resistance of a certain component in line with something and a small jumpper could most likely be made and plugged in to replace the mass I use but ehh.. no your not gonna blow anything up..even if yu plug the pc monitor in by itself.. I have tested this for you and have even had faulty cards outta box. best part is Andy is a greatguy and has some great products!!
-d88