I'm running a cable from back to front to power my 2 x 16 display I got from maplins. I'm using the 13 core if I remember rightly. I havent had any problems at all with it not working. Although mines only 2 x 16 not 4 x 20. I have wrote a simple VB program using a ocx I purchased which at the moment just displays the time / date and type of car. I will be playing further pulling infomation from RR soon so I can display lots more.