NEW YORK (CNNMoney.com) - Tech stocks got off to a fast start this year but hit a speed bump with earnings season -- a sign that investors have to be more careful than ever when investing in the sector.

"You have to be very, very specific," said Romeo Dator, co-manager of the All-American Equity Fund from U.S. Global Investors, which manages over $3 billion. "You can't just buy a handful of tech stocks and think they'll do well. There will definitely be winners and losers."

Intel's disappointing results sent shares stumbling.

After its recent earnings report, for example, Apple (down $0.55 to $78.49, Research) stock dipped despite strong results due to a lowered forecasts, though it didn't take nearly the beating that some other big-name tech stocks did.

Shares of Intel (down $0.13 to $22.27, Research) and Yahoo! (up $0.12 to $34.45, Research) got crushed, for example, after their results missed analysts' estimates and their outlooks disappointed many on Wall Street.

While some tech companies may be struggling in the short-term, the beating some stocks took owes more to overly high expectations from investors that from weak fundamentals, some investors say.

"These companies move at a fast clip; investors expect them to set certain targets and then meet or exceed them," said Sunil Reddy, senior portfolio manager at Cincinnati-based Fifth Third Asset Management.

Reddy remains optimistic on the tech sector, citing the fact that companies around the world are flush with cash and need to re-invest, which often translates into increased spending on technology, he said.

But he, like some other investors, offers a few caveats. He suggests owning a diversified portfolio of companies undergoing positive change – expanding margins, good top-line growth and earnings potential – and also recommends companies where expectations are not too high.

Richard Skaggs, vice president and co-portfolio manager of the Loomis Sayles Large-Cap Growth fund, noted that while things have been moving quickly in the tech sector in recent days, "Investors have moved back to a company-specific view rather than the broad-brush macro view that was dominating trading" after the Intel and Yahoo news.

Skaggs said Intel's results had investors worried that tech spending and PC shipments were in decline across the board. But a strong quarter from Intel rival Advanced Micro Devices helped eased those concerns.

Still, he said, his fund is taking a "stock by stock" view of the tech sector.

Techs started 2006 with a bang -- with the Nasdaq composite jumping 5.7 percent in the first seven sessions of the year -- but then came the start of earnings season.

The number one chipmaker delivered results that shocked Wall Street, missing its own revenue projections, issued just six weeks ago, and offering a lower-than-expected full-year forecast of single-digit sales growth. Shares fell 11 percent on the news and haven't recovered since.

Concerns about rival Advanced Micro Devices (down $0.93 to $36.20, Research) gaining share in the server and laptop markets -- both higher growth areas than the desktop computer market -- also led investors to take a cautious view of Intel for the near term.

Fifth Third's Reddy said that in Intel's case, the bad news is company-specific and not related to the tech sector overall.

"They are facing some good competition from AMD, which they haven't seen in literally 15, 20 years," he said. "AMD's results were a very striking contrast."

Striking indeed. AMD posted a quarterly profit that reversed a year-ago loss, and the chipmaker also issued an upbeat forecast. Revenue jumped 45 percent – and investors jumped for joy, sending shares up to $37, their highest point all year.

"Some people think AMD has a better mousetrap," said Skaggs, whose fund owns shares of AMD and sold its small position in Intel following the report. "Intel has issues. I'm sure they'll get them fixed... but in next three to six months, I think AMD is the preferred equity in an Intel/AMD pair."

Michael Church, whose Church Capital Management owns shares of Intel, said he is not adding to his position right now but feels the company's long-term story is in positive, given factors such as its deal to supply chips to Apple.

The same night Intel posted its disconcerting numbers, Yahoo! also sent investors stampeding for the exits. Despite reporting a 36 percent gain in quarterly profit, earnings per share came in a penny below Wall Street forecasts, and guidance also came in lower than expected, sending the shares plummeting.

Dator of U.S. Global Investors thinks Yahoo!'s guidance is likely accurate.

"They're losing market share to Google," he said. "Google is the search engine of choice for people who want to advertise on the Internet."

The day after Yahoo!'s miss, investors pounced on Apple for issuing a current-quarter forecast that missed expectations, despite a robust quarter in which the company announced record sales and earnings and nearly doubled its quarterly profit. But the news sent the stock tumbling to below $80 for the first time since last week, when Jobs announced that revenue had handily beat expectations.

Apple bulls -- and indeed, it's hard to find an Apple bear these days -- say the lower-than-hoped-for guidance means the company is simply trying to manage expectations appropriately in light of a seasonal drop-off in iPod sales for the post-December quarter as well as the product transition to the new, Intel-based Macs.

Said Dator, whose fund owns shares of Apple, "They'll still beat the guidance numbers; they're just downplaying expectations. But in terms of product portfolio, there is no one I can think of that has more exciting products that people want to buy."

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