At the close, the Dow Jones Industrial Average was down 0.3 percent, the broad S&P 500 index 1.1 percent and the tech-heavy Nasdaq Composite 2.2 percent.
Once again, several stocks strongly linked to AI - including AMD, Micron, Sandisk and VanEck Semiconductor - came under pressure.
Industry peer CoreWeave fell another 11.9 percent, leaving the stock down 25.2 percent for the week.
The AI frenzy that has shaken Wall Street all week stems from concerns about competition from China, as well as overvaluation and high debt levels at companies.
Michael Rosen, chief investment officer at advisory firm Angeles, is trying to calm investors:
"Of course, increased debt is something to note, continue to monitor and worry about if it reaches unreasonable levels. But we are not far from that at the moment," he tells CNBC.
Concerns are also being fueled by grim inflation figures for September, which have increased the risk of future interest rate hikes.
In addition, oil futures are climbing again. A barrel of North Sea oil (Brent) costs $109.5, up 3.4 percent on the day.
The Nasdaq has lost 4.5 percent overall this week - its worst week since June. The S&P 500 is down 1.2 percent this week.
The Dow, on the other hand, rose 0.6 percent.
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