The Globe and Mail reports in its Tuesday edition that Wall Street's main indexes closed lower on Monday, driven by a drop in artificial-intelligence leader Nvidia that weighed on tech stocks, as investors looked ahead to a crucial U.S. inflation report later this week. A Reuters dispatch to The Globe says that Canada's main stock index also ended lower, but the decline was limited by gains for resource shares after China pledged to stimulate its economy. Nvidia fell 2.5 per cent after China's market regulator launched an investigation into the chipmaker over suspected violation of anti-monopoly law, dragging the information technology sector down 0.45 per cent. Advanced Micro Devices slipped 5.7 per cent after BofA Global Research downgraded its rating on the stock, weighing on the Philadelphia Semiconductor Index, which slipped 0.87 per cent. In Toronto, the materials sector advanced 2.1 per cent. Gold and copper prices rose as China said it would take more action to boost its lethargic economy. Energy was up 0.4 per cent as the price of oil rose 1.4 per cent to $68.13 (U.S.) a barrel. Over all, the S&P/TSX Composite Index ended down 66.38 points at 25,625.42, after touching a record high of 25,843.20 intraday.