Wall Street isn't always moved by breaking news. More often, it's the anticipation that sets the mood, with investors spending hours waiting for a data point or earnings release that could nudge portfolios one way or another. Today, that pause revolves around Nvidia. The chipmaker, whose processors run everything from gaming rigs to artificial-intelligence systems, reports earnings after the bell. What would normally be a quarterly update now feels like a test of how much longer the tech rally can run.