U.S. stocks set for tough open Thursday

At 6:51 a.m. ET, Nasdaq and S&P were lower, with a comparison to fair value pointing to a negative start for Wall Street.

Hopes that the Federal Reserve will cut rates were hit after a report in the Wall Street Journal said the central bank may not rush to the rescue of investors.

Fed Chairman Bernanke wants to break the assumption that central bank will cut rates whenever there is turmoil in financial markets, the report said.

Stocks had rallied Wednesday on hopes that the central bank would intervene in markets. In a letter sent to Sen. Charles Schumer (D-N.Y.), Bernanke said the Fed was monitoring the trouble in financial markets and prepared to step in and take action if necessary.

The comments raised expectations that the Fed will cut rates and helped the Dow Jones industrial average gain nearly 250 points. stocks rebounded overnight, and major European markets rose in early trading on Thursday.

Investors will look for more clues about what the central bank intends to do with rates on Friday, when Bernanke is due to give a speech about monetary policy and housing in Jackson Hole, Wyoming.

On Thursday, they'll get more news on the health of the economy. The Commerce Department is due to provide an update on second-quarter gross domestic product at 8:30 a.m. ET.

Economists surveyed by Briefing.com expect GDP, the broadest measure of the nation's economic activity, to be revised higher to a 4.1 percent annual rate of growth for the second quarter ended June 30, up from its previous estimate of 3.4 percent.

Treasury prices rose, lowering the yield on the benchmark 10-year note to 4.54 percent from 4.57 percent late Wednesday. Bond prices and yields move in opposite directions.

Oil prices gained, with U.S. light crude for September delivery adding 35 cents to $73.86 a barrel.