Wall Street stocks mostly ticked lower on Wednesday, as investors await chipmaker Nvidia's earnings report after the closing bell.

Around 15 minutes into trading, the broad-based S&P 500 fell 0.2 percent to 5,616.13, while the tech-rich Nasdaq Composite Index slumped 0.5 percent to 17,674.05.

The Dow Jones Industrial Average was flat at 41,232.76.

The focus on chip titan Nvidia comes as markets try to gauge the health of the tech and AI sector.

The company has seen profits surge thanks to demand for its GPU chips, which have set the industry's pace in pushing new AI advances -- making it an indicator for the sector.

Nvidia shares slid 1.4 percent in early trading.

Apart from Nvidia, traders will also be monitoring an update to US second quarter GDP growth on Thursday and data on the Federal Reserve's favored inflation gauge on Friday.

While a US central bank rate cut is widely expected in September, upcoming economic indicators are watched for their potential bearing on how big the reductions could go.

Among individual companies, Nordstrom shares rose 5.4 percent after earnings that beat expectations.