You build it like a normal PC. Online retailers do the Atom motherboard with integrated Atom chip. Buy some ram, CD/DVD drive, Hard drive and micro atx case and bang them all together and bobs your uncle. 300watt is well sufficient to power it. I’ve read somewhere they that it will consume about 50watts in total depending on efficiency of components. I would recommend waiting for a more power efficient version of the atom motherboard to be released as it meant to be very power hungry compared to the chip itself.