US STOCKS-Wall St futures mixed as tech wobbles again, Tesla gains

Oct 16 (Reuters) - US stock index futures were mixed on Friday, as technology stocks came under fresh pressure on worries about cracks building in the AI trade, though a rise in Tesla shares and decline in oil prices offered support.

The electric vehicle maker TSLA.O rose 4.4% in premarket trading after unveiling a redesigned Roadster, powered by rocket-style thrusters, developed in collaboration with SpaceX SPCX.O, whose shares climbed 2.1%.

Cautionary signs persisted in the AI sector as Nvidia-backed CoreWeave CRWV.O slipped 4.1%, after Thursday's rebound, on lingering concerns about the data centre operator's debt load.

Other neocloud firms Nebius Group NBIS.O and Iren IREN.O dipped 2% each while chipmakers Micron Technology MU.O and Broadcom AVGO.O fell 1.7% and 0.4%, respectively.

AI stocks have cratered this week as investors who have crowded into bets all along the AI supply chain worry that data centre operators might not turn profitable in time to repay debts, particularly with borrowing costs expected to rise.

Some of these stocks have risen sharply this year, helping push benchmarks S&P 500 and Nasdaq to record highs as recently as last week.

"When you've this incredibly bullish narrative matched with incredibly bullish outcomes but the stock declines, that is the sort of technical signal that tells you there's too many people in the pool," said James Athey, fixed-income portfolio manager at Marlborough.

The selloff in AI stocks sparked a rotation into defensive sectors such as healthcare on Thursday, helping the main indexes close slightly higher.

Still, the S&P 500 and Nasdaq were set to post weekly losses as an AI-led rout, mixed earnings from big banks and inflation data weighed on sentiment through the week.

The Dow, however, remained on track for a weekly advance.

Markets increasingly expect the Federal Reserve to keep interest rates unchanged this month. Fed Chair Kevin Warsh said the US economy remained resilient and was benefiting from an AI-driven investment boom. He, however, noted the spending surge was boosting inflation.

At 6:21 a.m. ET, Dow E-minis were up 204 points, or 0.39%, and S&P 500 E-minis were up 12.5 points, or 0.16%. Nasdaq 100 E-minis were down 23.5 points, or 0.08%.

Further supporting risk appetite, oil prices fell nearly 1%, though Brent crude remained above the $100-a-barrel mark. O/R

Among other movers, Varonis Systems VRNS.O climbed 2.3% after Thoma Bravo's Proofpoint agreed to buy the data security firm in a $6.3 billion all-cash deal.