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Q3 GDP estimate more than expected

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Micron sees steeper Q2 loss, other chipmakers down

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CarMax down on pausing share buybacks

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Futures down: Dow 0.39%, S&P 0.53%, Nasdaq 0.75%

Dec 22 (Reuters) - Wall Street's main indexes were set to open lower on Thursday as fresh data underscored strength in the U.S. economy and aggravated concerns over the Federal Reserve's continued policy tightening.

The final estimate of third-quarter U.S. GDP revealed that gross domestic product increased at a 3.2% annualized rate, above the previous estimate of 2.9%.

Meanwhile, a Labor Department report showed the number of Americans filing for state unemployment benefits increased to 216,000 last week, much below economists' estimate of 222,000, indicating a still tight labor market.

"Third-quarter GDP estimate has been revised up much more than it was expected and is giving the futures a reason to decline ... if the economy is too strong, the Fed may have to raise rates by more than what was expected," said Robert Pavlik, senior portfolio manager at Dakota Wealth, Connecticut.

"You combine that with the weekly initial unemployment claims, it just fuels the talk of the Fed having to be more restrictive in their policy."

Wall Street's main indexes marked their biggest daily gain so far in December on Wednesday, with help from upbeat Nike Inc and FedEx Corp quarterly earnings, as well as improving consumer confidence and easing inflation expectations.

Fears of a recession following the U.S. central bank's prolonged interest rate hikes have weighed heavily on equities this year, with the benchmark S&P 500 set for annual declines of 18.6%, its worst such performance since the financial crisis of 2008.

The Fed struck a hawkish tone last week at its policy meeting by saying that it expects interest rates to remain higher for longer, sparking a selloff across stock markets.

The bets for a 25-basis point hike to 4.5%-4.75% in February by the Fed remained unchanged at 71.4% following the data on Thursday, although expectations for the terminal rate inched up marginally to 4.88% by May 2023.

At 8:41 a.m. ET, Dow e-minis were down 132 points, or 0.39%, S&P 500 e-minis were down 20.75 points, or 0.53%, and Nasdaq 100 e-minis were down 85.25 points, or 0.75%.

Micron Technology Inc slipped 4.3% in premarket trading after the chipmaker forecast a bigger-than-expected second-quarter loss, sparking declines in peers.

Nvidia Corp, Qualcomm Inc, Advanced Micro Devices Inc and Intel Corp were down between 0.7% and 1.8%.

CarMax Inc slid 13.3% after the used-vehicles retailer paused share buybacks following an 86% plunge in quarterly profit. (Reporting by Shubham Batra, Amruta Khandekar, Ankika Biswas and Johann M Cherian in Bengaluru; Editing by Shounak Dasgupta)