*U.S. stock index futures turned negative on Thursday after Goldman Sachs Group (GS.N) reported its third-quarter results.

* S&P 500 futures SPc1 fell 2.9 points and were below fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures DJc1 fell 17 points and Nasdaq 100 futures NDc1 lost 4.75 points.

Investment Goldman sachs U.S.