Abstract: Systems and methods for testing a multi-core processor may include comparing electromagnetic energy radiated from the multi-core processor while executing a specified set of instructions to reference values associated with multi-core processors having known numbers of operable cores. In various embodiments, average radiated power at a plurality of selected frequencies is compared to corresponding reference values to determine the number of functioning cores. In one embodiment, similarity between a test node and one or more reference nodes is determined using a Euclidean distance. The number of operable cores is determined according to a known number of operable cores associated with the closest reference node.