S&P 500 was at closing up 0.5 percent, which means a new record level for the broad index.
Nasdaq's technology-heavy composite index was at the same time up 0.9 percent, while Dow Jones industrial index was up 0.3 percent.
Semiconductor giant Nvidia announced on Thursday that it is investing $5 billion, over 46 billion kronor, in competitor Intel. The companies will initiate cooperation to develop advanced chips, which caused Intel's share to surge 23 percent.
Otherwise, it was primarily smaller companies that acted as locomotives. They often rely on more external financing for their operations and growth compared to the giants, writes CNBC.
The US central bank Federal Reserve announced on Wednesday that the interest rate is being lowered by 0.25 percentage points, a decision in line with expectations.
At the same time, dampening signals came about future interest rate cuts, which dashed investors' hopes of deeper relief and caused the broad index to close below zero.
