- US stock futures rose on a big increase in Nvidia sales projections, which fuelled advances in Asian tech companies but did not raise regional equities indexes.

- Japan, South Korea, Australia, and China all saw their stocks fall. Declines in Hong Kong's Hang Seng Index put the benchmark on track for a third day of losses of more than 1%.

- Taiwanese stocks soared, bucking the Asian trend, as Taiwan Semiconductor Manufacturing, which supplies Nvidia, surged 2.5%. Samsung  and SK Hynix both of South Korea, advanced.

- The downturn in Asia reflected cross winds as investors weighed the possibility of the United States defaulting on its debt, the likelihood of another Federal Reserve rate hike, central bank meetings in Seoul and Jakarta, and signs of weakening in China's economy.

- Gold lost an earlier gain, as the dollar reversed course to strengthen versus the yen after surging higher after Fitch downgraded US ratings. The ratings agency said the decision reflected the partisan debate over the debt ceiling, but it still anticipates a deal to avoid default.

- Nasdaq 100 futures rose 1.4%, retaining the majority of their early gains despite the Fitch report. The rise came after the underlying index fell 0.5% on Wednesday due to concerns about the debt-ceiling deadlock and uncertainty about the Fed's upcoming policy decision. Contracts for the S&P 500 rose 0.3%.

- Following the chipmaker's forecast that rising demand for artificial intelligence processors will fuel revenue growth, Nvidia shares jumped by roughly 25% in after-hours trade. The action represented an increase in market value of roughly $200 bln.