U.S. stock index futures pointed to a lower open on Friday after worse-than-expected quarterly results from computer maker Dell and homebuilder D.R. Horton underscored that the road to recovery would not be smooth.

D.R. Horton Inc (DHI.N) shed 6.6 percent to $11.44 in premarket trading after it reported a fourth-quarter loss that was wider than expected and said market conditions were still challenging. 

The homebuilder's results came in the same week data showed new housing starts fell to their lowest level in six months in October. 

Dell Inc (DELL.O) fell 7.6 percent to $14.67 a day after it reported third-quarter sales that missed estimates. 

Investors have been watching the technology sector closely, as it is considered one of the first groups to emerge from a recession. Technology shares were pummeled in Thursday's session after a bearish analyst comment on semiconductors.

There's a great deal of concern about the customer out there, and Dell only heightens that, said Tom Schrader, managing director of U.S. equity trading at Stifel Nicolaus Capital Markets in Baltimore.

The other weak results we've seen aren't going to bode well for the market either.

S&P 500 futures SPc1 fell 7.8 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 dropped 66 points, and Nasdaq 100 futures NDc1 slid 8.75 points.

Also weighing on stock futures was the dollar, which gained 0.6 percent against a basket of currencies .DXY.

Everyone is looking at the dollar right now, said Kim Caughey, senior equity research analyst at Fort Pitt Capital Group in Pittsburgh. Low interest rates are supposed to make investors want to take risks, but that's not happening. People remain very nervous about the economy.

The dollar pushed December crude oil futures down nearly 1 percent, extending Thursday's decline. 

Also Friday, food company JM Smucker Co (SJM.N) reported higher-than-expected quarterly profit and raised its full-year outlook, lifting its stock 4.7 percent to $56 premarket. 

Dow component General Electric Co (GE.N) fell 1.1 percent to $15.58 before the bell after the Financial Times reported GE and Vivendi SA (VIV.PA) were at least $1 billion apart in their valuation of Vivendi's stake in NBC Universal.