This is the new mainboard, it has some modifications from the original mainly on the power convertion 12v to 5v as the 7805 was not providing enough amperage. The converter needed is very cheap and available on the net. The mainboard provides 11 slots for module cards and 1 for debugging- expansion purposes. The 5v to 3.3v should suffice if you need to supply 3.3v to a device. You can use a Jumper cable to pass this voltage to any of the six extended pins.
