Wall Street advanced for a third straight day on Friday as the tech sector rose on upbeat outlooks, though weak trading volume hinted the rally lacks enthusiasm.

All three major stock indexes looked to post gains for the week after two straight weeks of declines. The S&P was on track to notch its best week in eight, raising renewed questions about how much upside potential was left.

Fundamentals are improving, but I'm not sure the economy will jump back on the high-speed rails to expansion like investors are hoping, said Andrew Wilkinson, senior market analyst at Interactive Brokers Group in Greenwich, Connecticut. I think expectations are going to be a little more sober heading into the future.

Trading volume has been weak, with Tuesday's session the lowest of the year, pointing to a lack of conviction.

Oracle Corp jumped 3.3 percent to $33.20 and was the Nasdaq's most actively traded name a day after forecasting a rise in new software sales for its current fiscal quarter. The outlook fueled hopes that a global resurgence in tech spending remains intact, prompting at least 12 brokerages to raise their price targets on the stock.

The S&P technology index <.GSPT> rose 0.5 percent on Friday, and is up more than 3 percent so far this quarter.

In a further boost to techs, Accenture rose 5.1 percent to $54.59 after the technology outsourcing and consulting company raised its outlook.

When you see big names like these beat expectations like this, it's very encouraging, said Michael Vogelzang, president and chief investment officer at Boston Advisors, which owns Oracle shares.

Oracle is taking share, which is great to see, but you don't post these numbers in a soft environment. The market is getting stronger.

The Dow Jones industrial average <.DJI> was up 62.55 points, or 0.51 percent, at 12,233.11. The Standard & Poor's 500 Index <.SPX> was up 6.86 points, or 0.52 percent, at 1,316.52. The Nasdaq Composite Index <.IXIC> was up 20.14 points, or 0.74 percent, at 2,756.56.

On the downside in tech shares, BlackBerry maker Research In Motion Ltd said earnings would slip as it spends heavily to launch its PlayBook tablet. The company's U.S.-listed shares sank 11 percent to $57.05.

The U.S. economy grew more quickly than previously estimated in the fourth quarter of 2010 as businesses restocked shelves to meet rising demand.

U.S. consumer sentiment in March fell to its lowest level in more than a year as gasoline and food prices rose, according to the latest consumer survey from Thomson Reuters and the University of Michigan.

Edwards Lifesciences Corp rose 4.7 percent to $89.37. Standard & Poor's said late Thursday the company would be added to the S&P 500 after the close of trading on March 31. On Friday, Madison Williams upgraded the stock to buy.

(Editing by Leslie Adler)