Electronic circutboard pattern noise?

it depends on how realistic you want the board to be, for instance, do you want the board to actually interact with ports, such as USB, or a generic serial connection type? if so, then first run a pathfinding algorithm from you power supply source, thru a transformer, and then thru a capacitor (basic DC conversion), to the power pins in the usb, making the usb have basic charging functions, then filter the serial ports of the usb thru capacitors that are tuned to filter off into different signals, and run these signals into the processing chip, or to transistors (basic switches), and have the return connected to a RAM chip, this provides you with the basic concepts of a circuit board, remember to include nodes in the pathfinding algorithm (nodes are the little copper dots that transfer electricity to the other side of a board). after you build that base-code, randomizing the position of the power supply, the processor, and the usb connection(or generic serial connection) will give you large amounts of difference