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* Futures: Dow up 0.06%, S&P up 0.03%, Nasdaq down 0.01%

Nov 22 (Reuters) - U.S. stock index futures were muted on Wednesday as shares of Nvidia slipped after the chip designer warned of a slowdown in China sales, while investor optimism about potential rate cuts from the Federal Reserve next year also waned.

Nvidia forecast overall revenue above Wall Street targets, but its shares fell 1% in premarket trading after the company said U.S. export curbs could lead to a steep drop in fourth-quarter sales in China.

"A very high bar has been set for Nvidia and because of concerns about trade tensions, there is some element of worry creeping back," said Susannah Streeter, head of money and markets at Hargreaves Lansdown.

At 5:02 a.m. ET, Dow e-minis were up 22 points, or 0.06%, S&P 500 e-minis were up 1.25 points, or 0.03%, and Nasdaq 100 e-minis were down 1.75 points, or 0.01%.

Investors also had an eye on the latest turn of events at OpenAI after the ChatGPT maker reached an agreement for Sam Altman to return as CEO days after his ouster. Shares of the startup's financial backer Microsoft edged 0.5% higher.

Big Tech stocks led a rebound in U.S. equities in November, with the S&P 500 coming within a whisker of its highest level this year, as signs of easing inflation boosted bets that the Fed was done with its interest rate hikes.

The benchmark index and the tech-heavy Nasdaq, however, snapped a five-session winning streak on Tuesday after minutes from the latest Fed meeting showed officials agreed to take a cautious approach to raising U.S. interest rates going forward.

The central bank's guarded approach is weighing on enthusiasm about rate cuts coming later, Streeter said.

Light trading volumes also impacted market moves ahead of the Thanksgiving holiday on Thursday.

Later in the day, investors will parse a number of economic reports for more clues on the strength of the U.S. economy and the outlook for interest rates.

Durable goods data for October and weekly jobless claims numbers are scheduled to be released at 8:30 am ET followed by a final reading of the University of Michigan's consumer sentiment index for November. (Reporting by Amruta Khandekar; Editing by Maju Samuel)