Stock markets mostly rose Thursday after the Federal Reserve cut interest rates and US chip giant Nvidia announced a $5 billion investment in struggling rival Intel.

Wall Street's S&P 500 and the tech-heavy Nasdaq opened higher as shares in Intel jumped more than 25 percent and Nvidia gained 2.7 percent in early deals.

The Dow, however, was flat while the dollar gained against other major currencies.

"Even if Intel needs handouts from its peers in Silicon Valley, investors like it," said Kathleen Brooks, research director at trading platform XTB.

Under the Nvidia-Intel deal, the companies will jointly develop chips for PCs and data centres.

The deal comes on the heels of the United States taking a 10-percent stake in Intel.

Investors were also reacting to Wednesday's US central bank

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