The Philadelphia semiconductor index hit its highest level in more than a year on Thursday and eyed its biggest one-day percentage gain in six months with artificial intelligence (AI) taking center stage after Nvidia Corp. wowed investors with financial targets that blew past analyst expectations.

The semi index was last up 6.3% after hitting its highest level since early April 2022 while chip designer Nvidia, its biggest gainer by far, was up 26.7% and trading at record levels with an intraday high of $394.80.

Nvidia late on Wednesday announced a second-quarter revenue target more than 50% above Wall Street estimates with plans to boost supply to meet surging demand for its artificial-intelligence chips, which are used to power popular services including ChatGPT.

Susquehanna International Group analyst Christopher Rolland described the beat as "unfathomable" in a research note titled "greatest beat of all time?" where he said he raised his price target to $450 from $350 for Nvidia, which last traded at $386.99.

"It looks like the new gold rush is upon us, and NVIDIA is selling all the picks and shovels," Rolland wrote.

Still, besides Nvidia, the biggest gainers in the chip index included NYSE listed shares of Nvidia chip manufacturer Taiwan Semiconductor, which were up 11.5%, power supply company Vicor Corp. was up more than 15%, and component supplier Monolithic Power, whose shares were up 16.4%.

Dylan Patel, an analyst with SemiAnalysis, said Monolithic Power is supplying power delivery modules to Nvidia's flagship AI chip, the H100.

In contrast, investors in rival Intel Corp. had the opposite reaction to Nvidia's news, sending shares in the chipmaker down 6.5% as Intel has been struggling to catch up with rivals like Nvidia.

"Anything with a hint of AI is up," said Bernstein analyst Stacy Rasgon. "Anything that is seen as a non-beneficiary, or god-forbid a AI loser, is down."

Also soaring on Thursday was rival Advanced Micro Devices , which is expected to release new chips that could help it compete with Nvidia in AI, later this year. AMD shares were up 10.7%.

Shares in Applied Materials, a supplier of chip manufacturing equipment, were up 5.8% and other companies involved in chip manufacturing process including ASLM Holdings and KLA Corp and Lam Research were up more than 5%.

In the 15 plus years he's been covering chips Bernstein's Rasgon said he's "never seen a guide like the one NVDA just put up with (fiscal second quarter) outlook that was by all accounts cosmological, and which annihilated expectations."