Ross Givens says Nvidia (NVDA), Supermicro (SMCI) were part of the 1st wave in the A.I. Boom. But now, he sees "backdoor" plays in the A.I. investment space such as nuclear power. Givens lists Nuscale (SMR), Nano Nuclear Energy (NNE) and Oklo Inc. (OKLO) among his A.I. second wave watch list.