Investor concerns and a lofty valuation have punished the chipmaker, but the future still looks bright.Nvidia (NVDA -7.55%) stock started off September not with a bang but with a whimper. Late last week, the company reported the results of its fiscal 2025 second quarter (ended July 28), and while the results were better than expected, they weren't as robust as some investors had hoped.The stock was under pressure again on Tuesday, falling as much as 8.4%. As of 12:27 p.m. ET, the stock was still down 7.8%.D ...