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Futures off: Dow 0.80%, S&P 500 0.94%, Nasdaq 1.13%

March 6 (Reuters) - U.S. stock index futures fell on

Thursday as uncertainty about an ongoing global trade war

clouded sentiment, while chip stocks took a beating after

Marvell Technology's ( MRVL ) broadly in-line forecast fanned worries of

slowing demand for AI infrastructure.

At 5:28 a.m. ET, Dow E-minis were down 344 points,

or 0.80%, S&P 500 E-minis were off 55 points, or 0.94%,

and Nasdaq 100 E-minis were lower 233.25 points, or

1.13%.

Marvell ( MRVL ) fell 15.5% in premarket trading after the

chipmaker forecast first-quarter sales in line with analysts'

average estimate, which failed to excite investors who had

expected stronger AI-driven growth.

Peer Broadcom ( AVGO ), which is expected to report results

after markets close, fell 3.4%, while Nvidia ( NVDA ) lost 1.6%

and Advanced Micro Devices ( AMD ) dropped 1.5%.

Megacaps such as Microsoft ( MSFT ) dipped 0.8% and Meta

and Alphabet declined 1.4% and 0.7%,

respectively.

Concerns that overspending and overcapacity in the U.S. AI

industry, in the face of China's cheaper DeepSeek models, have

been some factors that paused Wall Street's bull rally in

January. The tech-heavy Nasdaq is now down about 9% from

its record high hit in December.

Further, Alibaba's U.S-listed shares surged 2%

after the release of a new reasoning model that the conglomerate

said was on par with global hit DeepSeek's R1.

On the trade front, President Donald Trump exempted

automakers that comply with existing free trade agreement and

sources said the negotiations were ongoing. However, Trump made

it clear that he was not calling off his trade war, citing the

need for more border controls.

Automakers such as General Motors ( GM ), Ford and

Tesla were down over 1% after Wednesday's rise.

Against this backdrop, U.S. stocks have witnessed increased

volatility over the past few sessions.

Wall Street's main indexes closed higher over 1% on

Wednesday following Trump's announcement. However, the benchmark

S&P 500 is down this year and the Russell 200 index

has fallen nearly 6%. Futures tracking the domestically

focused index fell 1% on Thursday.

Multiple reports have suggested that tariff uncertainty has

resulted in individuals holding back on consumption and

corporate executives staying put on investment decisions,

sparking concerns of an impending economic slowdown as inflation

stays elevated.

A weekly report on jobless claims is due before markets open

but Friday's key payrolls data will be crucial for investors

trying to gauge the economy's health.

Traders now see the Federal Reserve lowering borrowing costs

by 25 basis points for the first time this year in June,

according to data compiled by LSEG.

Comments from policymakers Philadelphia Fed President

Patrick Harker, Governor Christopher Waller and Atlanta Fed

President Raphael Bostic, due later in the day, are likely to

strike a cautious tone on monetary policy easing.

Zscaler ( ZS ) rose 4.6% after raising its fiscal 2025

revenue forecast, signaling increasing demand for its

cloud-based cybersecurity services.