Marginal Defects, such as excessive voids in solder joints, dewetting, head-in-pillow and alike do not necessarily cause malfunctions, but may result in system performance issues, increased error rates, intermittent faults and other sporadic stability issues observed in certain operation modes, at certain workloads or manifesting in a seemingly stochastic manner. As a result, Marginal Defects may lead to No Fault/Trouble Found (NFF/NTF) scenarios.