In this video, I will talk about Nvidia's (NVDA -1.12%) second-quarter earnings and explain why we have seen its stock soar close to 240% this year with after-hours action. The markets are forward-looking, but even for a great business like Nvidia, valuation matters. Or does it?  

*Stock prices used were from the trading day of Aug. 23, 2023. The video was published on Aug. 23, 2023.