Codenamed Claremont, the CPU is an old Socket 7 Pentium design but has been modified to operate at a peak power consumption of less than 10mW. This is ultra-low on the ultra-low scale. Current ultra-low voltage CPUs use 15W or more.
Intel managed this by using a technique to apply voltage to a silicon chip called Near Threshold Voltage. This is based on the idea that processors have plenty of voltage to ensure that the transistors within switch with no trouble. However if you cut the applied voltage to be just above the required level.
According to Bit-Tech Intel didn’t have any motherboards lying around to use, so it had to search eBay to build the Asus P/I-P55TZP4 which it demoed the chip on. The boards had to be modified to allow for the ultra-low voltages.