SK Hynix led a broad rally in Asian technology shares on Wednesday, tracking a rebound in U.S. semiconductor names after a sharp sell-off earlier this week.

Shares of the South Korean memory chipmaker jumped over 11% in Seoul, building on previous session’s gains. Its rebound comes after the stock suffered its biggest-ever one-day decline on Monday, as investors locked in profits amid growing worries over AI spending.

Domestic rival Samsung Electronics rose 6.8%, while Seoul Semiconductor gained 6.4%.

The rally spread across Japan’s chip sector. Advantest climbed 4.2%, Lasertec gained 6.4%, Disco rose 2.8%, Tokyo Electron gained 0.9%, while SoftBank Group advanced 0.8%.

Taiwan Semiconductor Manufacturing Co was up 0.4%.

Asian tech gains follow a rebound on Wall Street, where semiconductor shares recovered after the previous session’s sell-off. The VanEck Semiconductor ETF rose 2.5%, with Micron Technology and Lam Research each climbing about 5%. Applied Materials and Teradyne gained more than 3%.

Despite Wednesday’s rebound, some investors warned that enthusiasm around AI-linked hardware stocks is becoming stretched. Jordan Cvetanovski, chairman and chief investment officer at Pella Funds, said demand for AI infrastructure remains strong as companies race to build computing capacity, but signs of speculative excess are beginning to emerge. 

“I’m starting to see some really concerning behavior in markets, he said on CNBC’s “Squawk Box Asia,” adding the volatility lately were “all the classic signs that we are in for a kind of rude shock coming in the AI space.”

Cvetanovski added that the AI spending boom has continued to overwhelmingly benefit hardware makers as companies race to build computing capacity.

“A lot of the action will be on the hardware side of things because this will be a race to the finish line. This will be an arms war,” he said. “Every company out there will need to get access to as much computers they can,” adding that “there will be supply shortages, as we’ve seen with the memory makers.”