STORY: U.S. stocks ended lower on Tuesday, with the Dow ticking down marginally, the S&P 500 shedding about half a percent and the tech-heavy Nasdaq losing nine-tenths of a percent.AI-related fears spooked the market after the Wall Street Journal reported that OpenAI missed internal targets for weekly users and revenue, raising concerns about its ability to support its massive spending on data centers.:: OracleThose worries brought down shares of Oracle by 4%, as the company is reported to have signed one of the biggest cloud deals ever with OpenAI.Chip stocks also dropped, with Nvidia, AMD and Broadcom ending sharply lower. Nvidia-backed CoreWeave also slid nearly 6%.AI will remain in the spotlight, with five of the Magnificent Seven megacap firms reporting quarterly earnings this week.Brian Mulberry, chief market strategist at Zacks Investment Management, said he's expecting strong results."What I think we are more than likely to find out is that the demise of software has been vastl...