Hong Kong (AFP) - Asian tech stocks sank again Friday as the rollercoaster ride that has characterised the week continued into the weekend, while crude prices edged back down after a brief rally sparked by news of an attack on a ship in the Strait of Hormuz.

Seoul and Tokyo took the brunt of the selling, tracking heavy losses on Wall Street where Apple led Magnificent Seven titans lower after announcing price hikes for laptops, tablets and other products citing rising costs.

The news caused a reverse on the Nasdaq and S&P 500, which had been boosted early on by blowout results from chip company Micron.

Amazon and Microsoft added to the downbeat mood after the European Union said they should face tougher digital competition rules because of their dominant position in cloud computing.

The tech sector has been the main driver of a surge to record highs across several markets globally amid an eye-watering boom in all things AI.

However, that euphoria appears to be waning of late, with company valuations looking stretched and traders questioning when firms will see a return on the trillions that has been invested.

“A few cracks have developed in the tech sector recently,” Miller Tabak’s Matt Maley said.

“Therefore, we believe it will be extremely important to watch how these hyperscalers trade going forward because if they continue to decline, it’s going to make it very tough for the rest of the market to advance.”

In early trade, Seoul’s Kospi dived more than four percent with chip giants SK hynix and Samsung down around five percent each.

The index has seen some wild moves this week – including Tuesday’s 10 percent drop – amid waxing and waning optimism over the AI boom.

Tokyo, which is also heavy with tech firms, shed more than three percent. Tech investment giant SoftBank plunged more than 12 percent as the New York Times reported that ChatGPT-maker OpenAI is considering holding off an initial public offering until 2027.

There were also steep losses in Hong Kong, Shanghai, Singapore and Taipei.

The losses came even as investors pared expectations for US interest rate hikes after data showed the Federal Reserve’s favoured gauge of inflation came in slightly lower than expected in May.

Oil prices resumed the downward shift that has marked the week, having risen around two percent Thursday on news that a cargo ship was damaged by an unknown projectile off Oman’s coast in Hormuz.

That prompted the International Maritime Organisation to halt an evacuation of crews trapped by the US-Iran war and sparked concerns about the shaky truce put in place as the two foes hold peace talks.

US media reported that Iran struck the ship in the strait, and the Iranian agency that claims to regulate traffic there issued a warning afterwards.

“Any passage through routes outside the framework designated by PGSA will not be covered by safe passage guarantees,” Persian Gulf Strait Authority said on X.

Iran has said it plans to introduce what it terms maritime service fees, which could complicate negotiations with Washington.

- Key figures around 0210 GMT -

Seoul - Kospi: DOWN 4.1 percent at 8,559.73

Tokyo - Nikkei 225: DOWN 3.5 percent at 69,820.28

Hong Kong - Hang Seng Index: DOWN 1.4 percent at 22,757.96

Shanghai - Composite: DOWN 1.1 percent at 4,075.78

West Texas Intermediate: DOWN 0.9 percent at $71.30 a barrel

Brent North Sea Crude: DOWN 0.9percent at $74.56 a barrel

Euro/dollar: DOWN at $1.1362 from $1.1374 on Thursday

Pound/dollar: DOWN at $1.3192 from $1.3199

Dollar/yen: DOWN at 161.80 yen from 161.81 yen

Euro/pound: DOWN at 86.12 pence from 86.18 pence

New York - Dow: UP 0.1 percent at 51.920.62 (close)

London - FTSE 100: UP 0.7 percent at 10,529.89 (close)