Stocks rose on Friday, with the Dow marking its best four-week winning streak since 1933, lifted by robust results from Research in Motion and comments by Fed Chairman Ben Bernanke, who said the central bank will do everything it can to stabilize banks.

Growing conviction that the worst is over for the economy helped Wall Street shrug off dour jobs data showing the highest unemployment rate since 1983.

The Nasdaq outperformed other indexes, helped by a 21 percent jump in the U.S.-listed stock of Research in Motion after the BlackBerry maker, a Canadian company, posted surprisingly strong results on brisk retail demand and gave a rosy outlook after Thursday's closing bell.

The move into technology reflects investors rotating funds into groups likely to benefit from an economic recovery, even though a turnaround in corporate profits in that sector might still be a few quarters away, said Michael Sheldon, chief market strategist at RDM Financial in Westport, Connecticut.

The Dow Jones industrial average <.DJI> climbed 39.51 points, or 0.50 percent, to 8,017.59. The Standard & Poor's 500 Index <.SPX> rose 8.12 points, or 0.97 percent, to 842.50. The Nasdaq Composite Index <.IXIC> gained 19.24 points, or 1.20 percent, to 1,621.87.

At Friday's close, the S&P 500 was up 24.5 percent from a 12-year low set on March 9, helped mainly by growing optimism that the economic slowdown is starting to moderate.

Research in Motion, a technology bellwether, surged 20.8 percent to $59.29 on the Nasdaq, while IBM ranked as the Dow's biggest gainer, up 1.4 percent at $102.22 on the New York Stock Exchange. The semiconductor index <.SOXX> rose 2.9 percent.

Financial stocks advanced after Bernanke, the Federal Reserve chairman, said the Fed will use all of its tools to stabilize markets.

Citigroup advanced 4 percent to $2.85, while Bank of America added 5 percent to $7.60.

An S&P index of financial companies' stocks <.GSPF> shot up 4.2 percent. Some analysts said investors may be covering short bets on financial stocks by buying back the shares.

Wall Street received more confirmation about deterioration in the labor market, when data showed the U.S. unemployment rate hit 8.5 percent, the highest level since 1983, as employers cut 663,000 jobs in March.

The numbers, though, were in line with economists' forecasts.

Another report from the Institute for Supply Management showed the U.S. services sector shrank for the sixth straight month in March as recession-weary consumers tightened their belts.

An index of pharmaceutical stocks <.DRG> fell 1.8 percent, but was still up more than 9 percent from last month's lows. Among the heaviest weights on the blue-chip Dow average were Johnson & Johnson , off 1.6 percent at $52.15, and Merck & Co , down 2 percent at $26.46.

Trading was moderate on the New York Stock Exchange, with about 1.48 billion shares changing hands, slightly below last year's estimated daily average of 1.49 billion, while on Nasdaq, about 2.13 billion shares traded, below last year's daily average of 2.28 billion.

Advancing stocks outnumbered declining ones on both the NYSE and the Nasdaq by a ratio of about 2 to 1.

(Additional reporting by Leah Schnurr Editing by Jan Paschal)

Ben Bernanke Ibm